#include<iostream>
#include<cmath>
using namespace std;
int main(){
	int m,t,s;
	cin>>m>>t>>s;
	int ans;
	if(t==0){
		cout<<m;
	}else if(s%t==0){
		ans=m-s/t;
		cout<<ans;
	}else{
		ans=m-ceil((double)s/t);
		cout<<ans;
	}
}