#!/usr/bin/env python3
# Poor's man Secret Santa

import random
import sys

def main():
    people = []
    
    for person in sys.stdin:
        people += [person.rstrip()]

    random.shuffle(people)    
    amount = len(people)
    for i in range(amount):
        print("{} -> {}".format(people[i], people[(i + 1) % amount]))

if __name__ == "__main__":
    main()