#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b,c;cin>>a>>b>>c;
	int n=int(b*1.0/a);
	int s=0;
	if((n+1)*a<c)s=a-1;
	else s=c-n*a;
	if(s==2)cout<<1;
	else cout<<s;
	return 0;
}