#include<bits/stdc++.h>
using namespace std;
int m,s,t;
  int main(){
	cin>>m>>t>>s;
	if(t==0)
	{
		cout<<0<<endl;
		return 0;
	}
	if(s%t==0)
	   cout<<max( m-s/t , 0)<<endl;
	else
	cout<<max( m-s/t-1 , 0)<<endl; 
	return 0;
}

#include<bits/stdc++.h> using namespace std; int m,s,t; int main(){ cin>>m>>t>>s; if(t0) { cout<<0<<endl; return 0; } if(s%t0) cout<<max( m-s/t , 0)<<endl; else cout<<max( m-s/t-1 , 0)<<endl; return 0; }