Codeforces Round #779 (Div. 2)A. Marin and Photoshoot_marin wants to know the minimum number of cosplaye-优快云博客

本文链接：https://blog.youkuaiyun.com/kai_wei_/article/details/123792813

本文介绍了一种算法，用于确定最少邀请多少名cosplayer加入初始队伍，以确保每段连续子序列中男性数量不超过女性，从而形成美丽的组照。通过分析样例，解析了算法的具体实现。

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A. Marin and Photoshoot

time limit per test
1 second
memory limit per test
256 megabytes

Today, Marin is at a cosplay exhibition and is preparing for a group photoshoot!

For the group picture, the cosplayers form a horizontal line. A group picture is considered beautiful if for every contiguous segment of at least 2 cosplayers, the number of males does not exceed the number of females (obviously).

Currently, the line has n cosplayers which can be described by a binary string s. The i-th cosplayer is male if $s_i $= 0 and female if s_i = 1. To ensure that the line is beautiful, you can invite some additional cosplayers (possibly zero) to join the line at any position. You can’t remove any cosplayer from the line.

Marin wants to know the minimum number of cosplayers you need to invite so that the group picture of all the cosplayers is beautiful. She can’t do this on her own, so she’s asking you for help. Can you help her?

Input

The first line contains a single integer$ t(1 \leq t \leq 10^3) $— the number of test cases.

The first line of each test case contains a positive integer$ n (1 \leq n \leq 100) $— the number of cosplayers in the initial line.

The second line of each test case contains a binary string s of length n — describing the cosplayers already in line. Each character of the string is either 0 describing a male, or 1 describing a female.

Note that there is no limit on the sum of n.

Output

For each test case, print the minimum number of cosplayers you need to invite so that the group picture of all the cosplayers is beautiful.

Example

input

Copy

9
3
000
3
001
3
010
3
011
3
100
3
101
3
110
3
111
19
1010110000100000101

output

Copy

Note

In the first test case, for each pair of adjacent cosplayers, you can invite two female cosplayers to stand in between them. Then, $\rightarrow 0110110.$

In the third test case, you can invite one female cosplayer to stand next to the second cosplayer. Then, $\rightarrow 0110.$

题目分析：

题目比较长，不太好懂，意思是每个连续的子序列（大于2）中男生不能多于女生（可以等于），也就是0不能多于1，看样例就能明白，比如010，看01，符合；10也符合；但是010不符合，所以加一个1，变成0110，那么怎么选子序列都符合。

#include<iostream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int tmp;
    string a;
    while(n--){
        cin>>tmp;
        cin>>a;
        int len=a.length();
        int sum=0;
        for(int i=0;i<len;i++){
            if(a[i]=='0'){
                if(a[i+1]=='0'){
                    sum+=2;
                }
                if(a[i+1]=='1'&&a[i+2]=='0'){
                    sum+=1;
                }
            }
        }
        cout<<sum<<endl;
    }
}