C++ brace initialization for integer array

Question

Why does brace-enclosed initialization not work for this integer array?

#include <iostream>
int main()
{
    int arr[2] = {0};
    for (int i = 0; i <= 2; i++)
        std::cout << arr[i] << " ";
}

The output is 0 0 -731153664. Why isn't it 0 0 0?

Because an array of X elements have indexes from 0 to X - 1. The size of the array is the number of elements, not the top index. Something which any book, tutorial or class should have mentioned. — Some programmer dude
– Some programmer dude, Commented Apr 9, 2020 at 5:01

john · Accepted Answer · 2020-04-09 05:01:31Z

1

Because there's only two elements in the array

for (int i = 0; i < 2; i++)

Printing arr[2] is undefined behaviour

answered Apr 9, 2020 at 5:01

john

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