水题 Codeforces Round #286 (Div. 2) A Mr. Kitayuta's Gift

题目传送门

 /*
     水题：vector容器实现插入操作，暴力进行判断是否为回文串
 */
 #include <cstdio>
 #include <iostream>
 #include <algorithm>
 #include <cstring>
 #include <string>
 #include <vector>
 using namespace std;

 const int MAXN = 1e4 + ;
 const int INF = 0x3f3f3f3f;
 vector<char> s;
 char ss[];

 bool check(void)
 {
     for (int i=, j=s.size ()-; i<j; ++i, --j)
         if (s[i] != s[j])    return false;
     return true;
 }

 int main(void)        //Codeforces Round #286 (Div. 2) A Mr. Kitayuta's Gift
 {
     //freopen ("A.in", "r", stdin);

     while (cin >> ss)
     {
         s.clear ();    bool flag = false;
         for (int i=; ss[i]; ++i)    s.push_back (ss[i]);
         for (int i=; i<=s.size (); ++i)
         {
             for (int j=; j<=; ++j)
             {
                 char ch = 'a' + j;
                 s.insert (s.begin () + i, ch);
                 if (check ())
                 {
                     flag = true;
                     for (int i=; i<s.size (); ++i)
                         cout << s[i];
                     cout << endl;    break;
                 }
                 else s.erase (s.begin () + i);
             }
             if (flag)    break;
         }

         if (!flag)    cout << "NA" << endl;
     }

     return ;
 }

 #include <cstdio>
 #include <iostream>
 #include <algorithm>
 #include <cstring>
 #include <string>
 #include <vector>
 using namespace std;

 const int MAXN = 1e4 + ;
 const int INF = 0x3f3f3f3f;

 bool ok(string x)
 {
     string ss = x;
     reverse (ss.begin (), ss.end ());
     return (ss == x);
 }

 int main(void)        //Codeforces Round #286 (Div. 2) A Mr. Kitayuta's Gift
 {
     //freopen ("A.in", "r", stdin);

     string s;
     cin >> s;

     int len = s.size ();
     for (int i=; i<=len; ++i)
     {
         for (char c='a'; c<='z'; ++c)
         {
             string x;
             for (int j=; j<i; ++j)    x += s[j];
             x += c;
             for (int j=i; j<len; ++j)    x += s[j];
             if (ok (x))    {cout << x << endl;    return ;}
         }
     }
     cout << "NA" << endl;

     return ;
 }

string 实现