Excuse me for my english, but I tried very hard to.=)

A: 379A - New Year Candles

Let cur_a amount of new candles, cur_b — amount of burnt out. Initially cur_a = a, cur_b = 0, after burning all cur_a new candles, amount of hours incremented by cur_a and cur_b +  = cur_a, lets make all burnt out candles into new cur_a = cur_b / b , repeat this algorithm until we can make at least one new candle.

Good day)

Welcome to the last Codeforces round in this year Good Bye 2013. This round will be unusual because it will be common for participants of both divisions.

The problems were prepared by authors Gerald Agapov (Gerald) and Svechnikov Artur (ikar). Pavel Kholkin (HolkinPV) and Vitaly Aksenov (Aksenov239) also help us to prepare the problems. Traditionally thanks to Michael Mirzayanov (MikeMirzayanov) for Codeforces and Polygon systems and Mary Belova (Delinur) for translating the problems.

UPD: Score distribution is similar to standard — 500-1000-1500-2000-2500-3000-3500

UPD2: Thanks to all participants, we hope everyone enjoyed prepared tasks. Problem analysis.

UPD3: Congratulations to the winners of the last round in this year. Rating will be changed in a few hours.
1. BaconLi
2. Egor
3. liympanda

We wish everyone good luck, high rating and excellent mood)