描述
After the Online Round contest, we believe that you have already known how to write programs in ACM contest.
For example, here‟s the analysis code of “A+B” problem.
Now after the start, you are supposed to do another easy problem.
For a string S, write a program to check whether it is a palindromic string.
Palindromice srings are strings that read the same forwards as backwards such as "abcba".
输入
There are multiple test cases.
For each case, the first line contains one integer n indicating the length of the string. And the second line contains a n-length string as described above.
1 <= n <= 100,000, the string may only contains lower case letters.
输出
For each case, print “YES” if the string is a palindromic or “NO” otherwise.
样例输入
3
aba
4
qwer
样例输出
YES
NO
回文是个好东西呐
#include <stdio.h> int main() { int n,j,i; char a[100001]; while(~scanf("%d",&n)) { getchar(); for(i=0;i<n;i++) { scanf("%c",&a[i]); } for(i=0,j=n-1;i<=(n-1)/2;i++,j--) { if(a[i]!=a[j]) break; } if(i>j) printf("YES "); else printf("NO "); } }