- Longest Palindromic Substring
Input: "babad"
Output: "bab"
Note: "aba" is also a valid answer.
Input: "cbbd"
Output: "bb"
class Solution {
private static int low;
private static int maxLen;
public String longestPalindrome(String s) {
int len=s.length();
if(len<2){
return s;
}
for(int i=0;i<len;i++){
extend(s,i,i);
extend(s,i,i+1);
}
return s.substring(low, low+maxLen);
}
private static void extend(String s, int j, int k) {
while(j>=0&&k<s.length()&&s.charAt(j)==s.charAt(k)){
j--;
k++;
}
if(maxLen<k-j-1){
low=j+1;
maxLen=k-j-1;
}
}
}
