days=input()
if(days=='monday' or days=='tuesday' or days=='wednesday' or days=='thrusday' or days=='friday'):
    print("no")
else:
    print("yes")

054d71b371d1311bb62454beed44e708b8beccf0
<mask token>

<mask token>
if days == 'monday' or days == 'tuesday' or days == 'wednesday' or days == 'thrusday' or days == 'friday':
    print('no')
else:
    print('yes')

days = input()
if days == 'monday' or days == 'tuesday' or days == 'wednesday' or days == 'thrusday' or days == 'friday':
    print('no')
else:
    print('yes')

days=input()
if(days=='monday' or days=='tuesday' or days=='wednesday' or days=='thrusday' or days=='friday'):
    print("no")
else:
    print("yes")
