#!/usr/bin/env python3.12

import re

def predict(numbers):
    print(numbers)
    result = []
    for i in range(0,len(numbers)-1):
        result.append(numbers[i+1]-numbers[i])
    if len(set(result)) == 1:
        print("ainult 1 tulemus")
        print (f"Tagsi {numbers[0]-result[0]}")
        return numbers[0]- result[0]
    print (f"Tagsi {numbers[0]-result[0]}")
    return numbers[0] - predict(result)


with open("data.txt") as file:
    lines = [line.rstrip() for line in file]

y = 0
for line in lines:
    temp = re.findall(r'\S+', line)
    numbers = list(map(int, temp))

    x = predict(numbers)
    print(x)
    y += x

print(y)