Mega GCD

#include<stdio.h>
#include <cmath>
#include <vector>
int gcd(int a, int b) {
    while (a != 0 && b != 0)
        if (a > b) a %= b;
        else b %= a;
        return a + b;
}
int main()
{
    int n = 0;
    int a = 0, b = 0;
    scanf_s("%d%d", &n, &b);
    for (int i = 1; i < n; i++)
    {
        scanf_s("%d", &a);
        b = gcd(a, b);
    }
    printf("%d", b);
    system("pause");
    return 0;
}