Initial commit

1 files changed, 55 insertions, 0 deletions

diff --git a/LongestPalindrome.java b/LongestPalindrome.java
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index 0000000..447bb27
--- /dev/null
+++ b/LongestPalindrome.java
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+import java.lang.*;
+import java.util.*;
+
+class LongestPalindrome {
+	public static String longestPalindrome(String s) {
+		// TODO: check if s length is 0 or 1
+		// TODO: find simpler solution
+
+		s = s.toLowerCase();
+		char[] arr = s.toCharArray();
+		String ans = null;
+
+		int i = 0;
+		int j = 0;
+		int max = 0;
+		// Odd case: "aba"
+		for (int a = 1; a < arr.length - 1; a++) {
+			i = a - 1;
+			j = a + 1;
+			while (i >= 0 && j < arr.length) {
+				if (arr[i] == arr[j]) {
+					if (j - i > max) {
+						max = j - i;
+						ans = s.substring(i, j + 1);
+					}
+					i--;
+					j++;
+				} else {
+					break;
+				}
+			}
+		}
+		// Even case: "abba"
+		for (i = 0, j = i + 1; i < arr.length - 1; i++) {
+			while (i >= 0 && j < arr.length) {
+				if (arr[i] == arr[j]) {
+					if (j - i > max) {
+						max = j - i;
+						ans = s.substring(i, j + 1);
+					}
+					i--;
+					j++;
+				} else {
+					break;
+				}
+			}
+		}
+		return ans;
+	}
+
+	public static void main(String[] args) {
+		String s = "kl;fadsjf;dalscbbciuporeqwrpo";
+		System.out.println(longestPalindrome(s));
+	}
+}