import sys
#input = sys.stdin.readline
#input = sys.stdin.buffer.readline #文字列はダメ
#sys.setrecursionlimit(1000000)
#import bisect
#import itertools
#import random
#from heapq import heapify, heappop, heappush
from collections import defaultdict 
#from collections import deque
#import copy
#import math
#from functools import lru_cache
#@lru_cache(maxsize=None)
#MOD = pow(10,9) + 7
#MOD = 998244353
#dx = [1,0,-1,0]
#dy = [0,1,0,-1]
#dx8 = [1,1,0,-1,-1,-1,0,1]
#dy8 = [0,1,1,1,0,-1,-1,-1]

#激ムズでは？

def main():
    N = int(input())
    Z = []
    for i in range(N):
        v,w = map(int,input().split())
        Z.append((v,w))
    
    for v,w in Z:
        if v == 1:
            print('Yes');exit()
    print('No')





if __name__ == '__main__':
    main()