From 653b59fa20feab5f3d433a9ae648602743da6d2d Mon Sep 17 00:00:00 2001
From: Ayush Yadav <56931013+AyushYadav29@users.noreply.github.com>
Date: Thu, 24 Oct 2019 12:37:34 +0530
Subject: [PATCH] Added Longest Palindrome Subsequence code
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Problem: Given a sequence, find the length of the longest palindromic subsequence in it.
As another example, if the given sequence is “BBABCBCAB”, then the output should be 7 as “BABCBAB” is the longest palindromic subseuqnce in it. “BBBBB” and “BBCBB” are also palindromic subsequences of the given sequence, but not the longest ones.
---
 .../pedrovgs/Longest_Palindrome_Subsequence   | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 src/main/java/com/github/pedrovgs/Longest_Palindrome_Subsequence

diff --git a/src/main/java/com/github/pedrovgs/Longest_Palindrome_Subsequence b/src/main/java/com/github/pedrovgs/Longest_Palindrome_Subsequence
new file mode 100644
index 00000000..3492c26e
--- /dev/null
+++ b/src/main/java/com/github/pedrovgs/Longest_Palindrome_Subsequence
@@ -0,0 +1,27 @@
+public class Longest_Palindrome_Subsequence {
+static int max(int x, int y) {
+if(x>y)
+return x;
+else
+return y;
+}
+static int lps(char s[], int i, int j) {
+
+if (i == j) {
+return 1;
+}
+if (s[i] == s[j] && i + 1 == j) {
+return 2;
+}
+if (s[i] == s[j]) {
+return lps(s, i + 1, j - 1) + 2;
+}
+return max(lps(s, i, j - 1), lps(s, i + 1, j));
+}
+public static void main(String[] args) {
+String s = "ABBDCACBAD";
+int n = s.length();
+System.out.print("The longest palindrome subsequence is "+l
+ps(s.toCharArray(), 0, n - 1));
+}
+}