CF673A Bear and Game

Bear Limak likes watching sports on TV. He is going to watch a game today. The game lasts $ 90 $ minutes and there are no breaks. Each minute can be either interesting or boring. If $ 15 $ consecutive minutes are boring then Limak immediately turns TV off. You know that there will be $ n $ interesting minutes $ t_{1},t_{2},...,t_{n} $ . Your task is to calculate for how many minutes Limak will watch the game.

The first line of the input contains one integer $ n $ ( $ 1

Print the number of minutes Limak will watch the game.

In the first sample, minutes $ 21,22,...,35 $ are all boring and thus Limak will turn TV off immediately after the $ 35 $ -th minute. So, he would watch the game for $ 35 $ minutes. In the second sample, the first $ 15 $ minutes are boring. In the third sample, there are no consecutive $ 15 $ boring minutes. So, Limak will watch the whole game.