题意：给你一个字符串，让你在里面寻找可不连续的字符串“xtCpc”，问有多少个

          题目有问题，给了个gdCpc   

          样例：输入：10 xtCxtCpcpc     输出：2

思路：只要保证每个字符前面出现的次数大于本字符出现的次数就好（想想为什么）

           为了保证字符顺序

#include<bits/stdc++.h>
using namespace std;
const int maxn=2e5+5;
char s[maxn];
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        scanf("%s",s);
        int x1=0,x2=0,x3=0,x4=0,x5=0,ans=0;
        for(int i=0;i<n;i++)
        {
            if(s[i]=='x') x1++;
            if(s[i]=='t'&&x2<x1) x2++;
            if(s[i]=='C'&&x3<x2) x3++;
            if(s[i]=='p'&&x4<x3) x4++;
            if(s[i]=='c'&&x5<x4) x5++;
            if(x1&&x2&&x3&&x4&&x5)
            {
                ans++;
                x1--;
                x2--;
                x3--;
                x4--;
                x5--;
            }
        }  
        printf("%d\n",ans);
    }
    return 0;
}

Hello GDCPC

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 1321    Accepted Submission(s): 163

 

Problem Description

You have a string of lowercase letters.You need to find as many sequence “gdCpc” as possible.But letters in the same position can only be used once。

 

 

Input

The input file contains two lines.

The first line is an integer n show the length of string.(1≤n≤2×105)

The second line is a string of length n consisting of lowercase letters and uppercase letters.

 

 

Output

The input file contains an integer show the maximum number of different subsequences found.

 

 

Sample Input

10

gdCgdCpcpc

 

 

Sample Output

2