Array

Question

Why have we got some result ? With index that not exist

#include <iostream>
using namespace std;

int main()
{
int arr[] = {11, 35, 62, 555, 989};
int sum = 0;

for (int x = 0; x < 15; x++) {
sum += arr[x];
}

cout << sum << endl;

return 0;
}

Answer 1

When using an array literal to initialize an array (providing the data in {}), the array is made the correct size to hold the given data. This array could also be initialized like this:
int arr[5] = { 11, 35, 62, 555, 989 };

C++ will not throw an error for using an array index that doesn't exist. Instead, you will retrieve a garbage value, which is why you still receive an answer.