Arpa and a research in Mexican wave

题意翻译

arpa正在研究“墨西哥波”。 体育场内有$N$名观众。他们在0点开始“墨西哥波”。 - 第一次，第一个观众站了起来。 - 第二次，第二个观众站了起来。 - …… - 在时间$k$，第k个观众站起来。 - 在时间$k+1$，第$k+1$名观众站立，第一名观众就坐。 - 在时间$k+2$，第$k+2$个观众站着，第二个观众坐着。 …… - 在时间n，第$n$个观众站着，第$n$个观众坐着。 - 在时间$n+1$，第$n+1-k$名观众就座。 …… - 在时间$n+k$时，第$n$个观众就坐。 ARPA想知道时间$T$时有多少观众站着。

题目描述

Arpa is researching the Mexican wave. There are $ n $ spectators in the stadium, labeled from $ 1 $ to $ n $ . They start the Mexican wave at time $ 0 $ . - At time $ 1 $ , the first spectator stands. - At time $ 2 $ , the second spectator stands. - $ ... $ - At time $ k $ , the $ k $ -th spectator stands. - At time $ k+1 $ , the $ (k+1) $ -th spectator stands and the first spectator sits. - At time $ k+2 $ , the $ (k+2) $ -th spectator stands and the second spectator sits. - $ ... $ - At time $ n $ , the $ n $ -th spectator stands and the $ (n-k) $ -th spectator sits. - At time $ n+1 $ , the $ (n+1-k) $ -th spectator sits. - $ ... $ - At time $ n+k $ , the $ n $ -th spectator sits. Arpa wants to know how many spectators are standing at time $ t $ .

输入输出格式

输入格式

The first line contains three integers $ n $ , $ k $ , $ t $ ( $ 1<=n<=10^{9} $ , $ 1<=k<=n $ , $ 1<=t<n+k $ ).

输出格式

Print single integer: how many spectators are standing at time $ t $ .

输入输出样例

输入样例 #1

10 5 3

输出样例 #1

3

输入样例 #2

10 5 7

输出样例 #2

5

输入样例 #3

10 5 12

输出样例 #3

3

说明

In the following a sitting spectator is represented as -, a standing spectator is represented as ^. - At $ t=0  $ ----------  number of standing spectators = 0. - At $ t=1  $ ^---------  number of standing spectators = 1. - At $ t=2  $ ^^--------  number of standing spectators = 2. - At $ t=3  $ ^^^-------  number of standing spectators = 3. - At $ t=4  $ ^^^^------  number of standing spectators = 4. - At $ t=5  $ ^^^^^-----  number of standing spectators = 5. - At $ t=6  $ -^^^^^----  number of standing spectators = 5. - At $ t=7  $ --^^^^^---  number of standing spectators = 5. - At $ t=8  $ ---^^^^^--  number of standing spectators = 5. - At $ t=9  $ ----^^^^^-  number of standing spectators = 5. - At $ t=10 $ -----^^^^^  number of standing spectators = 5. - At $ t=11 $ ------^^^^  number of standing spectators = 4. - At $ t=12 $ -------^^^  number of standing spectators = 3. - At $ t=13 $ --------^^  number of standing spectators = 2. - At $ t=14 $ ---------^  number of standing spectators = 1. - At $ t=15 $ ----------  number of standing spectators = 0.