Two Chickens (...)

Sadly, the prizes for the 2017 Sunrin spring school contest are paid out of Ukje's bank accounts. Whether or not they know how Ukje feels, the participants keep begging for no fewer than two chickens (...) as the first prize.

Ukje has two bank accounts. Given the balances of both accounts and the price of one chicken, find out whether Ukje can buy two chickens (...). He can combine the balances of both accounts to pay.

The first line contains the balances $A$ and $B$ of the two accounts. ($0 \le A, B \le 1\,000\,000\,000$)

The second line contains the price $C$ of one chicken. ($0 \le C \le 1\,000\,000\,001$)

If Ukje can buy two chickens (...), print the sum of the two account balances left after buying them. Otherwise, print the current sum of the two account balances.