S = input()

Target = ['k','e','y','n','c']
judge = True
for i in Target:
    if i in S:
        if i == 'e' and S.count(i) < 3:
            judge = False
            break
        else:
            pass
    else:
        judge = False

if judge == True:
    print('YES')
else:
    print('NO')
