#!/usr/bin/env python3

from collections import defaultdict

lines = (x.strip() for x in open("input.txt"))
nums = defaultdict(list)
TARGET = 30000000

for line in lines:
    print(line)
    turn = 0
    last_spoken = 0
    for starting in map(int, line.split(",")):
        nums[starting] = [turn]
        turn += 1
        last_spoken = starting
    for t in range(turn, TARGET):
        last = nums[last_spoken]
        if len(last) == 2:
            n = last[1] - last[0]
        else:
            n = 0
        nums[n] = nums[n][-1:] + [t]
        last_spoken = n
    print("->", last_spoken)