from collections import defaultdict
S = input()
s = 'kyoprotenkei90'
d = defaultdict(int)
for i in range(14):
    d[S[i]] += 1
for ss in s:
    if ss == 'k' or ss == 'o' or ss == 'e':
        if d[ss] != 2:
            print('No')
            exit()
    else:
        if d[ss] != 1:
            print('No')
            exit()
print('Yes')