T = 'kyoprotenkei90'
S = input()
D = dict()
for t in T:
    if t in D: D[t] += 1
    else: D[t] = 1
for s in S:
    if s in D:
        D[s] -= 1
        if D[s] == 0: del D[s]
    else:
        print('No')
        exit()
print('Yes')