A=list(map(int,input().split()))
S=sorted(set(A))
D=dict()
for i in range(len(S)):
  D[S[i]]=i
def f(x,y):
  return 1^(x&y)

for i in range(1<<6):
  x=[(i>>j)&1 for j in range(6)]
  if f(f(f(x[A[0]],x[A[1]]),x[A[2]]),f(f(x[A[3]],x[A[4]]),x[A[5]])):
    print('YES')
    exit()
print('NO')