#include<bits/stdc++.h>
using namespace std; 
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define length size()
#define endl "\n"
signed main(void){
 float a,b,c;
  cin >> a >> b >> c;
  cout << (int)(c*(ceil(a/b)))+0 << endl;
}

#include <stdio.h>
#include <stdlib.h>

#define MAX_INPUT_SIZE  1024

int
main(int argc, char* argv[])
{
    char input[MAX_INPUT_SIZE];

    int n = atoi(fgets(input, sizeof(input), stdin));
    int ret = n * n * n;

    printf("%d\n", ret);

    return 0;
}