from itertools import permutations

D = list(map(int, input().split()))

for v in permutations(range(7),7):
    cnt = 0
    for i in range(5):
        a = [D[v[i]],D[v[i+1]],D[v[i+2]]]
        if len(set(a))!=3:continue
        if max(a)!=D[v[i+1]] and min(a)!=D[v[i+1]]:continue
        if D[v[i]]>=D[v[i+2]]:continue
        cnt += 1
    if cnt==5:
        exit(print('YES'))
print('NO')