```cpp

include <bits/stdc++.h>
using namespace std;
long long a[100000001];
int main() {
	freopen("candy.in","r",stdin);
	freopen("candy.out","w",stdout);
	int x,n,l,r,ans=0,sum=0,j;
	cin>>n>>l>>r;
	int i;
	a[0]=l;
	x=l;
	for(i=1; i<=r-l; i++) {
		a[i]=x;
		x++;
	}
	a[r-l+1]=r;
	for(i=1; i<=r-l+1; i++) {
		ans=a[i]%n;
		sum=max(ans,sum);
	}
	cout<<sum;
	fclose(stdin);
	fclose(stdout);
	return 0;
}