1 class Solution {
2 public:
3 string longestPalindrome(string s) {
4 string result="";
5 int length=s.length();
6 int counter_Max=0;
7 int pos_Start=0,pos_End=0;
8
9 if(length<=2){
10 if(s[0]==s[1]) return s;
11 else{
12 result+=s[0];
13 return result;
14 }
15 }
16
17 // XXX...A...XXX style
18 for(int i=0;i<length;i++){
19 //search
20 int counter_Thisloop=1;
21 int j=i-1;
22 for(;(j>=0)&&((2*i-j)<length)&&(s[j]==s[2*i-j]);j--){
23 counter_Thisloop=counter_Thisloop+2;
24 }
25 if(counter_Thisloop>counter_Max){
26 counter_Max = counter_Thisloop;
27 pos_Start=j+1;
28 pos_End=2*i-j-1;
29 }
30 }
31 // XXX...AA...XXX style
32 for(int i=0;i<length;i++){
33 //search
34 int counter_Thisloop=0;
35 int j=i-1;
36 for(;(j>=0)&&((2*i-j-1)<length)&&(s[j]==s[2*i-j-1]);j--){
37 counter_Thisloop=counter_Thisloop+2;
38 }
39 if(counter_Thisloop>counter_Max){
40 counter_Max = counter_Thisloop;
41 pos_Start=j+1;
42 pos_End=2*i-j-2;
43 }
44 }
45
46 for(int k=pos_Start;k<=pos_End;k++){
47 result+=s[k];
48 }
49 return result;
50
51 }
52 };
