#!/usr/bin/env python3
# -*- coding: utf-8 -*-
if __name__ == '__main__':
    words = input("Введите предложение: ")
    a = 1
    for i in words:
        if a % 3 == 0:
            print(i)
        a = a + 1
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
if __name__ == '__main__':
    words = input("Введите предложение: ")
    a = 1
    for i in words:
        if a % 3 == 0:
            print(i)
        a = a + 1
#!/usr/bin/env python3 # -*- coding: utf-8 -*-