#include<bits/stdc++.h>

using namespace std;

signed main(){
	
	int l,r;
	cin >> l >> r;
	
	if(l == 1&&r == 0) cout << "Yes";
	else if(l == 0&&r == 1) cout << "No";
	else cout << "Invalid";
	
	return 0;
	
}

#include<bits/stdc++.h>

using namespace std;

int n;
int a[105][105];

signed main(){
	
	cin >> n;
	for(int i = 1;i <= n;++ i){
		for(int j = 1;j <= i;++ j){
			cin >> a[i][j];
		}
	}
	
	int w = 1;
	for(int i = 1;i <= n;++ i){
		if(w >= i) w = a[w][i];
		else w = a[i][w];
	}
	
	cout << w;
	
	return 0;
	
}