S = input()
cnt = 0
m_cnt = 0
res = []
for i, s in enumerate(S):
    if cnt == 6:
        if s == 'e':
            cnt = 7
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 5:
        if s == 'c':
            cnt = 6
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 4:
        if s == 'n':
            cnt = 5
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 3:
        if s == 'e':
            cnt = 4
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 2:
        if s == 'y':
            cnt = 3
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 1:
        if s == 'e':
            cnt = 2
        else:
            res.append([cnt, i])                
            cnt = 0
    if cnt == 0:
        if s == 'k':
            cnt = 1 
        else:
            res.append([cnt, i])                
            cnt = 0
res.append([cnt, i])

cnt2 = 0
m_cnt2 = 0
res2 = []
for i, s in enumerate(S[::-1]):
    if cnt2 == 6:
        if s == 'k':
            cnt2 = 7
        else:
            res2.append([cnt2, i])                
            cnt2 = 0
    if cnt2 == 5:
        if s == 'e':
            cnt2 = 6
        else:
            res2.append([cnt2, i])                
            cnt2 = 0
    if cnt2 == 4:
        if s == 'y':
            cnt2 = 5
        else:
            res2.append([cnt2, i])                
            cnt2 = 0
    if cnt2 == 3:
        if s == 'e':
            cnt2 = 4
        else:
            res2.append([cnt2, i])                
            cnt2 = 0
    if cnt2 == 2:
        if s == 'n':
            cnt2 = 3
        else:
            res2.append([cnt2, i])                
            cnt2 = 0

    if cnt2 == 1:
        if s == 'c':
            cnt2 = 2
        else:
            res2.append([cnt2, i])                
            cnt2 = 0

    if cnt2 == 0:
        if s == 'e':
            cnt2 = 1
        else:
            res2.append([cnt2, i])                
            cnt2 = 0
res2.append([cnt, i])

f = False
for i in res:
    if i[0] == 7:
        f = True
for i in res2:
    if i[0] == 7:
        f = True
for a in res:
    for b in res2:
        if a[1]+1 + b[1]+1 < len(S):
            if a[0] + b[0] >= 7:
                f = True
if f:
    print('YES')
else:
    print('NO')