Sample Input
Is PAT&TAP symmetric?
Sample Output
11
思路:
判断最长回文串。
代码
#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>
#include <cstring>
#include <cmath>
using namespace std;
#define endl '\n'
typedef long long ll;
int main()
{
string s;
getline(cin, s);
int maxn = 0;
for (int i = 0; i < s.size(); ++i)
{
for (int j = i + 1; j <= s.size(); ++j)
{
string s1 = s.substr(i, j);
string s2 = s1;
reverse(s2.begin(), s2.end());
if (s2 == s1 && s1.size() > maxn)
maxn = s1.size();
}
}
cout << maxn << endl;
return 0;
}