#include<bits/stdc++.h>
using namespace std;
int n,l,r,s=INT_MIN;
int main(){
	cin>>n>>l>>r;
	for(int i=l;i<=r;i++){
		if(i%n==n-1){
			cout<<n-1;
			return 0;
		}
		if(i%n>s)s=i%n;
	}
	cout<<s;
	return 0;
}