#include <iostream>
using namespace std;

int main() {
	// your code goes here
	int m, n, a, i, ami, ani;
	cin>>n>>m>>a;
	for (i=1;a<m;i++) ami=i;
	for (i=1;a<n;i++) ani=i;
	cout<<ami*ani;
	return 0;
}