CF556A.Case of the Zeros and Ones

普及/提高-

通过率：0%

AC君温馨提醒

该题目为【codeforces】题库的题目，您提交的代码将被提交至codeforces进行远程评测，并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供，我们无法保证该服务的稳定性，若提交后无反应，请等待一段时间后再进行重试。

题目描述

Andrewid the Android is a galaxy-famous detective. In his free time he likes to think about strings containing zeros and ones.

Once he thought about a string of length $n$ consisting of zeroes and ones. Consider the following operation: we choose any two adjacent positions in the string, and if one them contains 0, and the other contains 1, then we are allowed to remove these two digits from the string, obtaining a string of length $n-2$ as a result.

Now Andreid thinks about what is the minimum length of the string that can remain after applying the described operation several times (possibly, zero)? Help him to calculate this number.

输入格式

First line of the input contains a single integer $n$ ( $1<=n<=2·10^{5}$ ), the length of the string that Andreid has.

The second line contains the string of length $n$ consisting only from zeros and ones.

输出格式

Output the minimum length of the string that may remain after applying the described operations several times.

输入输出样例

输入#1
```
4
1100
```
输出#1
```
0
```
输入#2
```
5
01010
```
输出#2
```
1
```
输入#3
```
8
11101111
```
输出#3
```
6
```

说明/提示

In the first sample test it is possible to change the string like the following: .

In the second sample test it is possible to change the string like the following: .

In the third sample test it is possible to change the string like the following: .

首页