Театрална размер на решение codeforces

театрална размер на решение codeforces

//Hello Kumkum, This code is constributed by me!! Tanishqqqqqq
#include <bits/stdc++.h>
using namespace std;
int main()
{
    double n, m, a;
    cin >> n >> m >> a;
    cout << (long long)ceil(n / a) * (long long)ceil(m / a) << endl;
}