N = int(input())
uw = [list(map(int, input().split())) for _ in range(N)]

uw.sort()
if uw[i][0] == 1:
  print("Yes")
  exit()

if uw[i][0] != 2:
  print("No")
  exit()

print("No")
exit()
w2 = []
w3 = []

for u, w in uw:
  if u == 2:
    w2.append(w)
  elif u == 3:
    w3.append(w)

w2.sort()
w3.sort()