#include<bits/stdc++.h>
using namespace std;
bool cmp(int x,int y){
	return x>y;
}
int main(){
	int n,l,r,a[110],k=0;
	cin>>n>>l>>r;
	for(;l<=r;l++){
		int q=l;
		while(q>=n){
			q-=n;
		}
		a[k]=q;
		k++;
	}
	sort(a,a+k,cmp);
	cout<<a[0];
	return 0;
}

/**************************************************************
	Problem: 2401
	User: houshanglin
	Language: C
	Result: Compile Error
****************************************************************/