Given a number N, find the number of trailing zeroes in N!

trailing_zeroes.cpp

// Good explanation: https://www.purplemath.com/modules/factzero.htm
#include <bits/stdc++.h>
using namespace std;

uint64_t trailing_zeroes(uint64_t n) {
    uint64_t zeroes = 0;
    for(uint64_t i = 1ULL, factor = 5ULL; factor <= n; ++i, factor = pow(5, i))
        zeroes += (n / factor);
    return zeroes;
}

int main() {
    int t;  cin >> t;
    while(t--) {
        uint64_t n; cin >> n;
        cout << trailing_zeroes(n) << "\n";
    }
    return 0;
}