题目

本题链接：Palindrome subsequence

本博客给出本题截图：

AC代码

#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
#include <algorithm>

using namespace std;

const int N = 1010, mol = 10007;

int f[N][N];

int main()
{
    int T;
    cin >> T;
    int t = 1;
    while (T -- )
    {
        string s;
        cin >> s;
        int n = s.size();
        memset(f, 0, sizeof f);
        for (int i = 0; i < n; i ++ ) f[i][i] = 1;
        
        for (int len = 2; len <= n; len ++ )
            for (int i = 0; i + len - 1 < n; i ++ )
            {
                int j = i + len - 1;
                f[i][j] =  (f[i + 1][j] + f[i][j - 1] - f[i + 1][j - 1] + mol) % mol;
                if (s[i] == s[j]) f[i][j] = (f[i][j] + f[i + 1][j - 1] + 1 + mol) % mol;
            }
            
        printf("Case %d: %d\n", t ++, f[0][n - 1] % mol);
    }
    
    return 0;
}

  
 

  
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文章来源: chen-ac.blog.csdn.net，作者：辰chen，版权归原作者所有，如需转载，请联系作者。

原文链接：chen-ac.blog.csdn.net/article/details/121607642