#include <stdio.h>

int main()
{
    int m,t,s = 0;
    int n = 0;
    scanf("%d %d %d",&m,&t,&s);
    if(t == 0){
        n = m;
    }else if (s >= m*t){
        n = 0;
    }else{
        n = m - (s/t + (s%t != 0));
    }
    printf("%d",n);

    return 0;
}