<p></p>

#include <iostream>
#include <cmath>
using namespace std;

int main(){
    int n,x,y;
    cin>>n>>x>>y;
    int eaten=y/x;
    if(y%x!=0){
        eaten+=1;
    }
    int remaining=n-eaten;
    if (remaining<0){
        remaining=0;
    }
    cout<<remaining<<endl;
    return 0;
}

（答案仅供参考）