#include<bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c;
    cin>>a>>b>>c;
    if(b==0)cout<<a;
    else{
        int d=c%b;
        if(d!=0){
            c-=d;
            c/=b;
            c++;
            a-=c;
            cout<<a;
        }else{
            c/=b;
            a-=c;
            cout<<a;
        }
    }
    return 0;
}