Shubham has a binary string s. A binary string is a string containing only characters “0” and “1”.

He can perform the following operation on the string any amount of times:

Select an index of the string, and flip the character at that index. This means, if the character was “0”, it becomes “1”, and vice versa.
A string is called good if it does not contain “010” or “101” as a subsequence — for instance, “1001” contains “101” as a subsequence, hence it is not a good string, while “1000” doesn’t contain neither “010” nor “101” as subsequences, so it is a good string.

What is the minimum number of operations he will have to perform, so that the string becomes good? It can be shown that with these operations we can make any string good.

A string a is a subsequence of a string b if a can be obtained from b by deletion of several (possibly, zero or all) characters.

Input
The first line of the input contains a single integer t (1≤t≤100) — the number of test cases.

Each of the next t lines contains a binary string s (1≤|s|≤1000).

Output
For every string, output the minimum number of operations required to make it good.

Example
Input
7
001
100
101
010
0
1
001100
Output
0
0
1
1
0
0
2
Note
In test cases 1, 2, 5, 6 no operations are required since they are already good strings.

For the 3rd test case: “001” can be achieved by flipping the first character — and is one of the possible ways to get a good string.

For the 4th test case: “000” can be achieved by flipping the second character — and is one of the possible ways to get a good string.

For the 7th test case: “000000” can be achieved by flipping the third and fourth characters — and is one of the possible ways to get a good string.
思路：符合題目要求的字符串類型是：“1111110000000…”,“1111111111111111…”,“0000000001111111111111…”,"000000000000"這四種情況，但是總結起來就兩種：
①x個0+y個1.
②x個1+y個0.
我們求一下1的個數的前綴和，然后從頭開始遍歷，討論就可以了。
代碼如下：

#include<bits/stdc++.h> #define ll long long using namespace std;const int maxx=1e3+100; int sum[maxx]; string s;int main() {int t;scanf("%d",&t);while(t--){cin>>s;int n=s.length();int cnt=0;int ans=1e9;memset(sum,0,sizeof(sum));sum[0]=(s[0]=='1');for(int i=1;i<n;i++) sum[i]=sum[i-1]+(s[i]=='1');for(int i=0;i<n;i++) ans=min(ans,i+1-sum[i]+((sum[n-1]-sum[i])));//前i個都是0for(int i=0;i<n;i++) ans=min(ans,sum[i]+(n-i-1-(sum[n-1]-sum[i])));//前i個都是1cout<<ans<<endl;}return 0; }

努力加油a啊，(^o)/~

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