#include<stdio.h>
int main()
{
    int n = 0 , h = 0 , m = 0 , x = 0 ;
    scanf("%d %d %d",&n,&h,&m);
    x = m / h;
    if(m%h!=0)
    {
        x++;
    }
    printf("%d",n-x);
    return 0;
}