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Longest_Palindrome_in_a_String.java
56 lines (47 loc) · 1.31 KB
/
Longest_Palindrome_in_a_String.java
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import java.util.*;
class GFG {
public static void main (String[] args) {
Scanner sc = new Scanner(System.in);
int t = sc.nextInt();
while(t-- > 0){
String str = sc.next();
char[] arr = str.toCharArray();
LPS(arr, str.length() );
}
}
public static void LPS(char[] arr, int n){
boolean[][] mat = new boolean[n][n];
int maxLength = 1;
for(int i = 0; i<n; i++){
mat[i][i] = true;
}
int start = 0;
for(int i = 0; i< n-1; i++){
if( arr[i] == arr[i+1]){
mat[i][i+1] = true;
start = i;
maxLength = 2;
}
}
for(int i = 3; i<=n; i++){
for(int s = 0; s<n-i+1; s++){
int e = i + s - 1;
if( arr[s] == arr[e] && mat[s+1][e-1] ){
mat[s][e] = true;
if( i > maxLength){
start = s;
maxLength = i;
}
}
}
}
printSubStr(arr, start, start + maxLength - 1);
// return maxLength;
}
private static void printSubStr(char[] arr, int start, int end) {
for(int i = start; i<=end; i++){
System.out.print(arr[i]);
}
System.out.println();
}
}