#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b,c;
	cin>>a>>b>>c;
	int i=c/b;
	int z=a-i;
	if(c%b==0)
	{
		cout<<z;
	}
	else
	{
		cout<<z-1;
	}
	return 0;
}