# from random import randint

# with open('random_numbers.txt', 'w') as fil:
#     num = int(input('Enter the number of random numbers to be written to the file: '))
#     for i in range(num):
#         fil.write(f'{randint(1, 501)}\n')
#     fil.close()
mystr  = 'yes'
mystr += 'no'
mystr += 'yes'
print(mystr)