回文字符串

#include <cmath>
#include <vector>
#include <algorithm>
#include <bits/stdc++.h>
using namespace std;

int main() { 
    string s,t;
    cin>>s;
    t=s;
    reverse(s.begin(),s.end());
    int n=s.size();
    vector<vector<int>>f(n+1,vector<int>(n+1,0));
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++){
            if(s[i-1]==t[j-1])f[i][j]=f[i-1][j-1]+1;
            else f[i][j]=max(f[i-1][j],f[i][j-1]);
        }
     cout<<n-f[n][n]<<endl;
    

    return 0;
}