题解:
n/a*m/a
都要向上取整
代码:
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
__int64 n,m,a;
__int64 up(__int64 x,__int64 y)
{
if (x%y==)return x/y;
return x/y+;
}
int main()
{
scanf("%I64d%I64d%I64d",&n,&m,&a);
printf("%I64d",up(n,a)*up(m,a));
return ;
}