I am trying to implementing Karatsuba's algorithm from wikipedia and I cannot continue to code since I do not know to how to split an integer into lower-half and upper-half. For example, if we have an integer 223, then it should be split into two integer 22 and 3.
How I might do this?
so it has to be something like
num1 = 223;
some magical stuff happening here!
low1 = 22;
low2 = 3;
Thank you very much I really appreciate your help!
low1 = num1 / 10;
low2 = num1 % 10;
This is the gist of what you're trying to accomplish. I'm not familiar with the algorithm and what exactly you're trying to do, so extra logic will almost certainly be required, but this is a good starting point.
You can use the modulus (%) operator to extract digits from a number. For example
12345 % 10 = 5
12345 % 100 = 45
12345 % 1000 = 345
And so on. Hope this helps.
you can use the modulus (%) operator to remove out the last number of an integer
int num1 = 223;
int num2 = num1%10;
num2 = 3 in this case
%2 doesn't return the last number (it can only return 0 or 1). And the phrase "remove out"? The original number remains unmodified.I would suggest this algorithm to split an integer :
int i = 233678546; /* The integer you would like to split */
int digitNumber = String.valueOf(i).length(); /* use java.math.Math.log10 if you need a more mathematical approach */
double val = Math.pow(10.0, (double)(digitNumber / 2));
int div = new Double(val).intValue();
int left = i / div;
int right = i % div;
StringBuilder sb = new StringBuilder();
sb.append("Value : ");
sb.append(i);
sb.append('\n');
sb.append("Left : ");
sb.append(left);
sb.append('\n');
sb.append("Right : ");
sb.append(right);
sb.append('\n');
System.out.println(sb.toString());
