#include<bits/stdc++.h> using namespace std; int main(){ int n,x,y; cin>>n>>x>>y; if(y%x>0){ if(n-y/x-1>=0){ cout<<n-y/x-1; }else{ cout<<0; } }else if(n-y/x>=0){ cout<<n-y/x; }else{ cout<<0; } }