HackerRank – Algorithm – Warmup – Diagonal Difference

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int main()
{
    int n = 0, difference = 0, tmp = 0;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            cin >> tmp;
            if (j == i) {
                difference += tmp;
            }
            if (j == n - 1 - i) {
                difference -= tmp;
            }
        }
    }
    difference = abs(difference);
    std::cout << difference << std::endl;
    return 0;
}