﻿ Java exercises: Find longest Palindromic Substring within a string - w3resource # Java String Exercises: Find longest Palindromic Substring within a string

## Java String: Exercise-32 with Solution

Write a Java program to find longest Palindromic Substring within a string.

Pictorial Presentation: Sample Solution:

Java Code:

``````import java.util.*;
public class Main {
static void printSubStr(String str1, int l, int h) {
System.out.println(str1.substring(l, h + 1));
}

static int longPalSubstr(String str1) {
int n = str1.length();
boolean table[][] = new boolean[n][n];
int mLength = 1;
for (int i = 0; i < n; ++i)
table[i][i] = true;
int strt = 0;
for (int i = 0; i < n - 1; ++i) {
if (str1.charAt(i) == str1.charAt(i + 1)) {
table[i][i + 1] = true;
strt = i;
mLength = 2;
}
}
for (int k = 3; k <= n; ++k) {
for (int i = 0; i < n - k + 1; ++i) {
int j = i + k - 1;
if (table[i + 1][j - 1] && str1.charAt(i) == str1.charAt(j)) {
table[i][j] = true;

if (k > mLength) {
strt = i;
mLength = k;
}
}
}
}
System.out.print("The longest palindrome substring in the given string is; ");
printSubStr(str1, strt, strt + mLength - 1);
return mLength;
}
public static void main(String[] args) {
String str1 = "thequickbrownfoxxofnworbquickthe";
System.out.println("The given string is: " + str1);
System.out.println("The length of the palindromic substring is: " + longPalSubstr(str1));
}
}
```
```

Sample Output:

```The given string is: thequickbrownfoxxofnworbquickthe
The longest palindrome substring in the giv
en string is; brownfoxxofnworb
The length of the palindromic substring is: 16
```

Flowchart: Java Code Editor:

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