Given a string, you are supposed to output the length of the longest symmetric sub-string. For example, given Is PAT&TAP symmetric?, the longest symmetric sub-string is s PAT&TAP s, hence you must output 11.
Each input file contains one test case which gives a non-empty string of length no more than 1000.
For each test case, simply print the maximum length in a line.
Is PAT&TAP symmetric?
11
题意：
输入一个字符串，求该字符串中最长对称子串的长度。
题解：
穷举搜索，既要考虑 baab这种偶数类型的，也要考虑abcba这种技术类型的。
AC代码：
#include<iostream> #include<algorithm> #include<vector> #include<queue> #include<map> #include<string> #include<cstring> using namespace std; string a; int main(){ getline(cin,a); int len=a.length(); int mx=1; //先偶数 int r=0,l=1; int k; for(r=0;r<len;r++) { l=r+1; k=0; int rr=r; int ll=l; while(rr>=0&&ll<len&&a[rr]==a[ll]){ k+=2; rr--;ll++; } mx=max(k,mx); } //再奇数 for(r=0;r<len;r++) { l=r+2; k=1; int rr=r; int ll=l; while(rr>=0&&ll<len&&a[rr]==a[ll]){ k+=2; rr--;ll++; } mx=max(k,mx); } cout<<mx<<endl; return 0; }
PAT 甲级 1040 Longest Symmetric String (25 分)（字符串最长对称字串,遍历）
原文：https://www.cnblogs.com/caiyishuai/p/11437962.html