a=list(map(int,input().split()))
def op(x,y):
    return 1-(x&y)
for bit in range(2**6):
    p=dict()
    for i in range(6):
        p[a[i]]=(bit>>i)&1
    ans1=op(p[a[0]],p[a[1]])
    ans1=op(ans1,p[a[2]])

    ans2 = op(p[a[3]], p[a[4]])
    ans2 = op(ans2, p[a[5]])

    ans=op(ans1,ans2)
    if ans==1:
        print("YES")
        exit()
print("NO")