C++ || Simple Multi Digit, Decimal & Negative Number Infix To Postfix Conversion & Evaluation

February 05, 2021 admin No comments

The following is sample code which demonstrates the implementation of a multi digit, decimal, and negative number infix to postfix converter and evaluator using C++.

The program demonstrated on this page has the ability to convert and evaluate a single digit, multi digit, decimal number, and/or negative number infix equation. So for example, if the the infix equation of (19.87 * -2) was entered into the program, the converted postfix expression of 19.87 -2 * would display to the screen, as well as the final evaluated answer of -39.74.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

How To Convert Infix To Postfix How To Evaluate A Postfix Expression

1. Overview

The program demonstrated on this page is different from a previous implementation of the same type in that this version does not use a Finite State Machine during the conversion process, which simplifies the implemetation!

This program has the following flow of control:

• Get an infix expression from the user • Convert the infix expression to postfix & isolate all of the math operators, multi digit, decimal, negative and single digit numbers that are found in the postfix expression • Evaluate the postfix expression by breaking the infix string into tokens found from the above step • Display the evaluated answer to the screen

The above steps are implemented below.

2. Infix To Posfix Conversion & Evaluation





		
		
			Multi Digit Infix To Postfix Conversion & Evaluation
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 31, 2014
//    Updated: Feb 5, 2021
//    Taken From: http://programmingnotes.org/
//    File: InToPostEval.cpp
//    Description: The following demonstrates the implementation of an infix to
//      postfix converter and evaluator. This program has the ability to
//      convert and evaluate multi digit, decimal, negative and positive values
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <string>
#include <vector>
#include <stack>
#include <algorithm>
#include <exception>
#include <stdexcept>

// function prototypes
void displayDirections();
std::string convertInfixToPostfix(std::string infix);
bool isMathOperator(char token);
int orderOfOperations(char token);
double evaluatePostfix(const std::string& postfix);
double calculate(char mathOperator, double value1, double value2);
bool isNumeric(char value);
bool isNumeric(std::string value);
std::vector<std::string> split(const std::string& source, const std::string& delimiters = " ");
std::string replaceAll(const std::string& source
    , const std::string& oldValue, const std::string& newValue);

int main() {
    // declare variables
    std::string infix = "";

    // display directions to user
    displayDirections();

    try {
        // get data from user
        std::cout << "\nPlease enter an Infix expression: ";
        std::getline(std::cin, infix);

        // convert infix to postfix
        std::string postfix = convertInfixToPostfix(infix);

        std::cout << "\nThe Infix expression = " << infix;
        std::cout << "\nThe Postfix expression = " << postfix << std::endl;

        // evaluate the postfix string
        double answer = evaluatePostfix(postfix);

        std::cout << "\nFinal answer = " << answer << std::endl;
    } catch (std::exception& e) {
        std::cout << "\nAn error occurred: " + std::string(e.what()) << std::endl;
    }

    std::cin.get();
    return 0;
}// end of main

void displayDirections() {
// this function displays instructions to the screen
    std::cout << "\n==== Infix To Postfix Conversion & Evaluation ====\n"
        << "\nMath Operators:\n"
        << "+ || Addition\n"
        << "- || Subtraction\n"
        << "* || Multiplication\n"
        << "/ || Division\n"
        << "% || Modulus\n"
        << "^ || Power\n"
        << "$ || Square Root\n"
        << "s || Sine\n"
        << "c || Cosine\n"
        << "t || Tangent\n"
        << "- || Negative Number\n"
        << "Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23))\n";
    // ((sin(-4^5)*1.4)/(sqrt(23+2)--2.8))*(cos(1%2)/(7.28*.1987)^(tan(23)))
}// end of displayDirections

std::string convertInfixToPostfix(std::string infix) {
// this function converts an infix expression to postfix
        // declare function variables
    std::string postfix;
    std::stack<char> charStack;

    // remove all whitespace from the string
    infix.erase(std::remove_if(infix.begin(), infix.end(), [](char c) {
        return std::isspace(static_cast<unsigned char>(c));
    }), infix.end());

    // negate equations marked with '--'
    infix = replaceAll(infix, "(--", "(");

    // automatically convert negative numbers to have the ~ symbol.
    // this is done so we can distinguish negative numbers and the subtraction symbol
    for (unsigned x = 0; x < infix.length(); ++x) {
        if (infix[x] != '-') {
            continue;
        }
        if (x == 0 || infix[x - 1] == '(' || isMathOperator(infix[x - 1])) {
            infix[x] = '~';
        }
    }

    // loop thru array until there is no more data
    for (unsigned x = 0; x < infix.length(); ++x) {
        // place numbers (standard, decimal, & negative)
        // numbers onto the 'postfix' string
        if (isNumeric(infix[x])) {
            if (postfix.length() > 0 && !isNumeric(postfix.back())) {
                if (!std::isspace(postfix.back())) {
                    postfix += " ";
                }
            }
            postfix += infix[x];

        } else if (std::isspace(infix[x])) {
            continue;

        } else if (isMathOperator(infix[x])) {
            if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                postfix += " ";
            }
            // use the 'orderOfOperations' function to check equality
            // of the math operator at the top of the stack compared to
            // the current math operator in the infix string
            while ((!charStack.empty()) &&
                (orderOfOperations(charStack.top()) >= orderOfOperations(infix[x]))) {
                // place the math operator from the top of the
                // stack onto the postfix string and continue the
                // process until complete
                if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                    postfix += " ";
                }
                postfix += charStack.top();
                charStack.pop();
            }
            // push the remaining math operator onto the stack
            charStack.push(infix[x]);
        }
        // push outer parentheses onto stack
        else if (infix[x] == '(') {
            charStack.push(infix[x]);

        } else if (infix[x] == ')') {
            // pop the current math operator from the stack
            while ((!charStack.empty()) && (charStack.top() != '(')) {
                if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                    postfix += " ";
                }
                // place the math operator onto the postfix string
                postfix += charStack.top();
                // pop the next operator from the stack and
                // continue the process until complete
                charStack.pop();
            }

            // pop '(' symbol off the stack
            if (!charStack.empty()) {
                charStack.pop();
            } else {
                // no matching '('
                throw std::invalid_argument{ "PARENTHESES MISMATCH" };
            }
        } else {
            throw std::invalid_argument{ "INVALID INPUT" };
        }
    }

    // place any remaining math operators from the stack onto
    // the postfix array
    while (!charStack.empty()) {
        if (charStack.top() == '(' || charStack.top() == ')') {
            throw std::invalid_argument{ "PARENTHESES MISMATCH" };
        }
        if (postfix.length() > 0 && !std::isspace(postfix.back())) {
            postfix += " ";
        }
        postfix += charStack.top();
        charStack.pop();
    }

    // replace all '~' symbols with a minus sign
    postfix = replaceAll(postfix, "~", "-");

    return postfix;
}// end of convertInfixToPostfix

bool isMathOperator(char token) {
// this function checks if operand is a math operator
    switch (std::tolower(token)) {
        case '+': case '-': case '*': case '/':
        case '%': case '^': case '$': case 'c':
        case 's': case 't':
            return true;
            break;
        default:
            return false;
            break;
    }
}// end of isMathOperator

int orderOfOperations(char token) {
// this function returns the priority of each math operator
    int priority = 0;
    switch (std::tolower(token)) {
        case 'c': case 's': case 't':
            priority = 5;
            break;
        case '^': case '$':
            priority = 4;
            break;
        case '*': case '/': case '%':
            priority = 3;
            break;
        case '-':
            priority = 2;
            break;
        case '+':
            priority = 1;
            break;
    }
    return priority;
}// end of orderOfOperations

double evaluatePostfix(const std::string& postfix) {
// this function evaluates a postfix expression
    // declare function variables
    double answer = 0;
    std::stack<double> doubleStack;

    // split string into tokens to isolate multi digit, negative and decimal
    // numbers, aswell as single digit numbers and math operators
    auto tokens = split(postfix);

    // display the found tokens to the screen
    //for (unsigned x = 0; x < tokens.size(); ++x) {
    //    std::cout<< tokens.at(x) << std::endl;
    //}

    std::cout << "\nCalculations:\n";

    // loop thru array until there is no more data
    for (unsigned x = 0; x < tokens.size(); ++x) {
        auto token = tokens[x];

        // push numbers & negative numbers onto the stack
        if (isNumeric(token)) {
            doubleStack.push(std::atof(token.c_str()));
        }
        // if expression is a math operator, pop numbers from stack
        // & send the popped numbers to the 'calculate' function
        else if (isMathOperator(token[0]) && (!doubleStack.empty())) {
            double value1 = 0;
            double value2 = 0;
            char mathOperator = static_cast<unsigned char>(std::tolower(token[0]));

            // if expression is square root, sin, cos,
            // or tan operation only pop stack once
            if (mathOperator == '$' || mathOperator == 's' || mathOperator == 'c' || mathOperator == 't') {
                value2 = 0;
                value1 = doubleStack.top();
                doubleStack.pop();
                answer = calculate(mathOperator, value1, value2);
                doubleStack.push(answer);

            } else if (doubleStack.size() > 1) {
                value2 = doubleStack.top();
                doubleStack.pop();
                value1 = doubleStack.top();
                doubleStack.pop();
                answer = calculate(mathOperator, value1, value2);
                doubleStack.push(answer);
            }
        } else {
            // this should never execute, & if it does, something went really wrong
            throw std::invalid_argument{ "INVALID POSTFIX STRING" };
        }
    }
    // pop the final answer from the stack, and return to main
    if (!doubleStack.empty()) {
        answer = doubleStack.top();
    }
    return answer;
}// end of evaluatePostfix

double calculate(char mathOperator, double value1, double value2) {
// this function carries out the actual math process
    double ans = 0;
    switch (std::tolower(mathOperator)) {
        case '+':
            std::cout << value1 << mathOperator << value2;
            ans = value1 + value2;
            break;
        case '-':
            std::cout << value1 << mathOperator << value2;
            ans = value1 - value2;
            break;
        case '*':
            std::cout << value1 << mathOperator << value2;
            ans = value1 * value2;
            break;
        case '/':
            std::cout << value1 << mathOperator << value2;
            ans = value1 / value2;
            break;
        case '%':
            std::cout << value1 << mathOperator << value2;
            ans = ((int)value1 % (int)value2) + std::modf(value1, &value2);
            break;
        case '^':
            std::cout << value1 << mathOperator << value2;
            ans = std::pow(value1, value2);
            break;
        case '$':
            std::cout << char(251) << value1;
            ans = std::sqrt(value1);
            break;
        case 'c':
            std::cout << "cos(" << value1 << ")";
            ans = std::cos(value1);
            break;
        case 's':
            std::cout << "sin(" << value1 << ")";
            ans = std::sin(value1);
            break;
        case 't':
            std::cout << "tan(" << value1 << ")";
            ans = std::tan(value1);
            break;
        default:
            ans = 0;
            break;
    }
    std::cout << " = " << ans << std::endl;
    return ans;
}// end of calculate

std::vector<std::string> split(const std::string& source, const std::string& delimiters) {
    std::size_t prev = 0;
    std::size_t currentPos = 0;
    std::vector<std::string> results;

    while ((currentPos = source.find_first_of(delimiters, prev)) != std::string::npos) {
        if (currentPos > prev) {
            results.push_back(source.substr(prev, currentPos - prev));
        }
        prev = currentPos + 1;
    }
    if (prev < source.length()) {
        results.push_back(source.substr(prev, std::string::npos));
    }
    return results;
}// end of split

std::string replaceAll(const std::string& source
    , const std::string& oldValue, const std::string& newValue) {
    if (oldValue.empty()) {
        return source;
    }
    std::string newString;
    newString.reserve(source.length());
    std::size_t lastPos = 0;
    std::size_t findPos;
    while (std::string::npos != (findPos = source.find(oldValue, lastPos))) {
        newString.append(source, lastPos, findPos - lastPos);
        newString += newValue;
        lastPos = findPos + oldValue.length();
    }
    newString += source.substr(lastPos);
    return newString;
}// end of replaceAll

bool isNumeric(char value) {
    return std::isdigit(value) || value == '.' || value == '~';
}// end of isNumeric

bool isNumeric(std::string value) {
    for (unsigned index = 0; index < value.length(); ++index) {
        if (index == 0 && value[index] == '-' && value.length() > 1) {
            continue;
        }
        if (!isNumeric(value[index])) {
            return false;
        }
    }
    return true;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 31, 2014
//    Updated: Feb 5, 2021
//    Taken From: http://programmingnotes.org/
//    File: InToPostEval.cpp
//    Description: The following demonstrates the implementation of an infix to
//      postfix converter and evaluator. This program has the ability to
//      convert and evaluate multi digit, decimal, negative and positive values
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <cctype>
#include <string>
#include <vector>
#include <stack>
#include <algorithm>
#include <exception>
#include <stdexcept>
 
// function prototypes
void displayDirections();
std::string convertInfixToPostfix(std::string infix);
bool isMathOperator(char token);
int orderOfOperations(char token);
double evaluatePostfix(const std::string& postfix);
double calculate(char mathOperator, double value1, double value2);
bool isNumeric(char value);
bool isNumeric(std::string value);
std::vector<std::string> split(const std::string& source, const std::string& delimiters = " ");
std::string replaceAll(const std::string& source
    , const std::string& oldValue, const std::string& newValue);
 
int main() {
    // declare variables
    std::string infix = "";
 
    // display directions to user
    displayDirections();
 
    try {
        // get data from user
        std::cout << "\nPlease enter an Infix expression: ";
        std::getline(std::cin, infix);
 
        // convert infix to postfix
        std::string postfix = convertInfixToPostfix(infix);
 
        std::cout << "\nThe Infix expression = " << infix;
        std::cout << "\nThe Postfix expression = " << postfix << std::endl;
 
        // evaluate the postfix string
        double answer = evaluatePostfix(postfix);
 
        std::cout << "\nFinal answer = " << answer << std::endl;
    } catch (std::exception& e) {
        std::cout << "\nAn error occurred: " + std::string(e.what()) << std::endl;
    }
 
    std::cin.get();
    return 0;
}// end of main
 
void displayDirections() {
// this function displays instructions to the screen
    std::cout << "\n==== Infix To Postfix Conversion & Evaluation ====\n"
        << "\nMath Operators:\n"
        << "+ || Addition\n"
        << "- || Subtraction\n"
        << "* || Multiplication\n"
        << "/ || Division\n"
        << "% || Modulus\n"
        << "^ || Power\n"
        << "$ || Square Root\n"
        << "s || Sine\n"
        << "c || Cosine\n"
        << "t || Tangent\n"
        << "- || Negative Number\n"
        << "Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23))\n";
    // ((sin(-4^5)*1.4)/(sqrt(23+2)--2.8))*(cos(1%2)/(7.28*.1987)^(tan(23)))
}// end of displayDirections
 
std::string convertInfixToPostfix(std::string infix) {
// this function converts an infix expression to postfix
        // declare function variables
    std::string postfix;
    std::stack<char> charStack;
 
    // remove all whitespace from the string
    infix.erase(std::remove_if(infix.begin(), infix.end(), [](char c) {
        return std::isspace(static_cast<unsigned char>(c));
    }), infix.end());
 
    // negate equations marked with '--'
    infix = replaceAll(infix, "(--", "(");
 
    // automatically convert negative numbers to have the ~ symbol.
    // this is done so we can distinguish negative numbers and the subtraction symbol
    for (unsigned x = 0; x < infix.length(); ++x) {
        if (infix[x] != '-') {
            continue;
        }
        if (x == 0 || infix[x - 1] == '(' || isMathOperator(infix[x - 1])) {
            infix[x] = '~';
        }
    }
 
    // loop thru array until there is no more data
    for (unsigned x = 0; x < infix.length(); ++x) {
        // place numbers (standard, decimal, & negative)
        // numbers onto the 'postfix' string
        if (isNumeric(infix[x])) {
            if (postfix.length() > 0 && !isNumeric(postfix.back())) {
                if (!std::isspace(postfix.back())) {
                    postfix += " ";
                }
            }
            postfix += infix[x];
 
        } else if (std::isspace(infix[x])) {
            continue;
 
        } else if (isMathOperator(infix[x])) {
            if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                postfix += " ";
            }
            // use the 'orderOfOperations' function to check equality
            // of the math operator at the top of the stack compared to
            // the current math operator in the infix string
            while ((!charStack.empty()) &&
                (orderOfOperations(charStack.top()) >= orderOfOperations(infix[x]))) {
                // place the math operator from the top of the
                // stack onto the postfix string and continue the
                // process until complete
                if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                    postfix += " ";
                }
                postfix += charStack.top();
                charStack.pop();
            }
            // push the remaining math operator onto the stack
            charStack.push(infix[x]);
        }
        // push outer parentheses onto stack
        else if (infix[x] == '(') {
            charStack.push(infix[x]);
 
        } else if (infix[x] == ')') {
            // pop the current math operator from the stack
            while ((!charStack.empty()) && (charStack.top() != '(')) {
                if (postfix.length() > 0 && !std::isspace(postfix.back())) {
                    postfix += " ";
                }
                // place the math operator onto the postfix string
                postfix += charStack.top();
                // pop the next operator from the stack and
                // continue the process until complete
                charStack.pop();
            }
 
            // pop '(' symbol off the stack
            if (!charStack.empty()) {
                charStack.pop();
            } else {
                // no matching '('
                throw std::invalid_argument{ "PARENTHESES MISMATCH" };
            }
        } else {
            throw std::invalid_argument{ "INVALID INPUT" };
        }
    }
 
    // place any remaining math operators from the stack onto
    // the postfix array
    while (!charStack.empty()) {
        if (charStack.top() == '(' || charStack.top() == ')') {
            throw std::invalid_argument{ "PARENTHESES MISMATCH" };
        }
        if (postfix.length() > 0 && !std::isspace(postfix.back())) {
            postfix += " ";
        }
        postfix += charStack.top();
        charStack.pop();
    }
 
    // replace all '~' symbols with a minus sign
    postfix = replaceAll(postfix, "~", "-");
 
    return postfix;
}// end of convertInfixToPostfix
 
bool isMathOperator(char token) {
// this function checks if operand is a math operator
    switch (std::tolower(token)) {
        case '+': case '-': case '*': case '/':
        case '%': case '^': case '$': case 'c':
        case 's': case 't':
            return true;
            break;
        default:
            return false;
            break;
    }
}// end of isMathOperator
 
int orderOfOperations(char token) {
// this function returns the priority of each math operator
    int priority = 0;
    switch (std::tolower(token)) {
        case 'c': case 's': case 't':
            priority = 5;
            break;
        case '^': case '$':
            priority = 4;
            break;
        case '*': case '/': case '%':
            priority = 3;
            break;
        case '-':
            priority = 2;
            break;
        case '+':
            priority = 1;
            break;
    }
    return priority;
}// end of orderOfOperations
 
double evaluatePostfix(const std::string& postfix) {
// this function evaluates a postfix expression
    // declare function variables
    double answer = 0;
    std::stack<double> doubleStack;
 
    // split string into tokens to isolate multi digit, negative and decimal
    // numbers, aswell as single digit numbers and math operators
    auto tokens = split(postfix);
 
    // display the found tokens to the screen
    //for (unsigned x = 0; x < tokens.size(); ++x) {
    //    std::cout<< tokens.at(x) << std::endl;
    //}
 
    std::cout << "\nCalculations:\n";
 
    // loop thru array until there is no more data
    for (unsigned x = 0; x < tokens.size(); ++x) {
        auto token = tokens[x];
 
        // push numbers & negative numbers onto the stack
        if (isNumeric(token)) {
            doubleStack.push(std::atof(token.c_str()));
        }
        // if expression is a math operator, pop numbers from stack
        // & send the popped numbers to the 'calculate' function
        else if (isMathOperator(token[0]) && (!doubleStack.empty())) {
            double value1 = 0;
            double value2 = 0;
            char mathOperator = static_cast<unsigned char>(std::tolower(token[0]));
 
            // if expression is square root, sin, cos,
            // or tan operation only pop stack once
            if (mathOperator == '$' || mathOperator == 's' || mathOperator == 'c' || mathOperator == 't') {
                value2 = 0;
                value1 = doubleStack.top();
                doubleStack.pop();
                answer = calculate(mathOperator, value1, value2);
                doubleStack.push(answer);
 
            } else if (doubleStack.size() > 1) {
                value2 = doubleStack.top();
                doubleStack.pop();
                value1 = doubleStack.top();
                doubleStack.pop();
                answer = calculate(mathOperator, value1, value2);
                doubleStack.push(answer);
            }
        } else {
            // this should never execute, & if it does, something went really wrong
            throw std::invalid_argument{ "INVALID POSTFIX STRING" };
        }
    }
    // pop the final answer from the stack, and return to main
    if (!doubleStack.empty()) {
        answer = doubleStack.top();
    }
    return answer;
}// end of evaluatePostfix
 
double calculate(char mathOperator, double value1, double value2) {
// this function carries out the actual math process
    double ans = 0;
    switch (std::tolower(mathOperator)) {
        case '+':
            std::cout << value1 << mathOperator << value2;
            ans = value1 + value2;
            break;
        case '-':
            std::cout << value1 << mathOperator << value2;
            ans = value1 - value2;
            break;
        case '*':
            std::cout << value1 << mathOperator << value2;
            ans = value1 * value2;
            break;
        case '/':
            std::cout << value1 << mathOperator << value2;
            ans = value1 / value2;
            break;
        case '%':
            std::cout << value1 << mathOperator << value2;
            ans = ((int)value1 % (int)value2) + std::modf(value1, &value2);
            break;
        case '^':
            std::cout << value1 << mathOperator << value2;
            ans = std::pow(value1, value2);
            break;
        case '$':
            std::cout << char(251) << value1;
            ans = std::sqrt(value1);
            break;
        case 'c':
            std::cout << "cos(" << value1 << ")";
            ans = std::cos(value1);
            break;
        case 's':
            std::cout << "sin(" << value1 << ")";
            ans = std::sin(value1);
            break;
        case 't':
            std::cout << "tan(" << value1 << ")";
            ans = std::tan(value1);
            break;
        default:
            ans = 0;
            break;
    }
    std::cout << " = " << ans << std::endl;
    return ans;
}// end of calculate
 
std::vector<std::string> split(const std::string& source, const std::string& delimiters) {
    std::size_t prev = 0;
    std::size_t currentPos = 0;
    std::vector<std::string> results;
 
    while ((currentPos = source.find_first_of(delimiters, prev)) != std::string::npos) {
        if (currentPos > prev) {
            results.push_back(source.substr(prev, currentPos - prev));
        }
        prev = currentPos + 1;
    }
    if (prev < source.length()) {
        results.push_back(source.substr(prev, std::string::npos));
    }
    return results;
}// end of split
 
std::string replaceAll(const std::string& source
    , const std::string& oldValue, const std::string& newValue) {
    if (oldValue.empty()) {
        return source;
    }
    std::string newString;
    newString.reserve(source.length());
    std::size_t lastPos = 0;
    std::size_t findPos;
    while (std::string::npos != (findPos = source.find(oldValue, lastPos))) {
        newString.append(source, lastPos, findPos - lastPos);
        newString += newValue;
        lastPos = findPos + oldValue.length();
    }
    newString += source.substr(lastPos);
    return newString;
}// end of replaceAll
 
bool isNumeric(char value) {
    return std::isdigit(value) || value == '.' || value == '~';
}// end of isNumeric
 
bool isNumeric(std::string value) {
    for (unsigned index = 0; index < value.length(); ++index) {
        if (index == 0 && value[index] == '-' && value.length() > 1) {
            continue;
        }
        if (!isNumeric(value[index])) {
            return false;
        }
    }
    return true;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

The following is sample output.

====== RUN 1 ======
==== Infix To Postfix Conversion & Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root s || Sine c || Cosine t || Tangent - || Negative Number Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) Please enter an Infix expression: 12/3*9 The Infix expression = 12/3*9 The Postfix expression = 12 3 / 9 * Calculations: 12/3 = 4 4*9 = 36 Final answer = 36 ====== RUN 2 ====== ==== Infix To Postfix Conversion & Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root s || Sine c || Cosine t || Tangent - || Negative Number Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) Please enter an Infix expression: -150.89996 - 87.56643 The Infix expression = -150.89996 - 87.56643 The Postfix expression = -150.89996 87.56643 - Calculations: -150.9-87.5664 = -238.466 Final answer = -238.466 ====== RUN 3 ====== ==== Infix To Postfix Conversion & Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root s || Sine c || Cosine t || Tangent - || Negative Number Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) Please enter an Infix expression: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) The Infix expression = ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) The Postfix expression = -4 5 ^ s 1.4 * 23 2 + $ -2.8 - / 1 2 % c 7.28 .1987 * 23 t ^ / * Calculations: -4^5 = -1024 sin(-1024) = 0.158533 0.158533*1.4 = 0.221947 23+2 = 25 √25 = 5 5--2.8 = 7.8 0.221947/7.8 = 0.0284547 1%2 = 1 cos(1) = 0.540302 7.28*0.1987 = 1.44654 tan(23) = 1.58815 1.44654^1.58815 = 1.79733 0.540302/1.79733 = 0.300614 0.0284547*0.300614 = 0.00855389 Final answer = 0.00855389 ====== RUN 4 ====== ==== Infix To Postfix Conversion & Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root s || Sine c || Cosine t || Tangent - || Negative Number Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) Please enter an Infix expression: (1987 + 1991) * -1 The Infix expression = (1987 + 1991) * -1 The Postfix expression = 1987 1991 + -1 * Calculations: 1987+1991 = 3978 3978*-1 = -3978 Final answer = -3978 ====== RUN 5 ====== ==== Infix To Postfix Conversion & Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root s || Sine c || Cosine t || Tangent - || Negative Number Sample Infix Equation: ((s(-4^5)*1.4)/($(23+2)--2.8))*(c(1%2)/(7.28*.1987)^(t23)) Please enter an Infix expression: (1+(2*((3+(4*5))*6))) The Infix expression = (1+(2*((3+(4*5))*6))) The Postfix expression = 1 2 3 4 5 * + 6 * * + Calculations: 4*5 = 20 3+20 = 23 23*6 = 138 2*138 = 276 1+276 = 277 Final answer = 277

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Posted in: Advanced, C++ Tags: array, c++, for loop, if/else, infix, postfix

C++ || Simple Multi Digit, Decimal & Negative Number Infix To Postfix Conversion & Evaluation

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