Educational Codeforces Round 49 (Rated for Div. 2)A. Palindromic Twist

http://codeforces.com/problemset/problem/1027/A

abs()的意思是求绝对值的意思

#include
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int n,i,j;
        string s;
        cin>>n>>s;
        int flas=1;
        for(i=0,j=n-1; i