#include "bits/stdc++.h"
using namespace std;


int main(){
	int m,t,s;
	cin>>m>>t>>s;
	if(t==0){cout<<0;return 0;}
	else{
		double a=s/t;
		ceil(a);
		cout<<m-a;
	}
	
	
	
	//return 1;	
}