feat: add 1143. Longest Common Subsequence

Author: nphausg

.gitignore

@@ -21,3 +21,4 @@
 
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
+src/.DS_Store

.idea/codeStyles/Project.xml

@@ -16,29 +16,30 @@
 LeetCode is the best platform to help you enhance your skills, expand your knowledge and prepare for technical
 interviews.
 
-https://leetcode.com/nphau
+https://leetcode.com/nphausg
 
 🔥 Easy 🔥🔥 Medium 🔥🔥🔥 Hard
 
 ## 💎 Coding Challenge
 
-| Challenge  | Level  |  Java | Kotlin | Link
-|---|---|---|---|---
-| ValidParentheses  | 🔥 |  [Solution](src/sg/nphau/leetcode/easy/ValidParentheses.java) | - | [20](https://leetcode.com/problems/valid-parentheses)
-| Remove Duplicates  | 🔥 |  [Solution](src/sg/nphau/leetcode/easy/RemoveDuplicates.java) | - | [26](https://leetcode.com/problems/remove-duplicates-from-sorted-array)
-| Remove Element  | 🔥 |  [Solution](src/sg/nphau/leetcode/easy/RemoveElement.java) | - | [27](https://leetcode.com/problems/remove-element)
-| Concatenation Of Array  | 🔥 |  [Solution](src/sg/nphau/leetcode/easy/ConcatenationArray.java) | - | [1929](https://leetcode.com/problems/concatenation-of-array)
-| Letter Combinations of a Phone Number  | 🔥🔥 |  [Solution](src/sg/nphau/leetcode/medium/LetterCombinations.java) | - | [17](https://leetcode.com/problems/letter-combinations-of-a-phone-number)
-| Decode Ways | 🔥🔥 |  [Solution](src/sg/nphau/leetcode/medium/DecodeWays.java) | - | [91](https://leetcode.com/problems/decode-ways)
-| Find K Closest Elements | 🔥🔥 |  [Solution](src/sg/nphau/leetcode/medium/FindClosestElements.java) | - | [658](https://leetcode.com/problems/find-k-closest-elements)
-| First Missing Positive | 🔥🔥🔥 |  [Solution](src/sg/nphau/leetcode/hard/FirstMissingPositive.java) | [Solution](src/sg/nphau/leetcode/hard/FirstMissingPositive.kt) | [41](https://leetcode.com/problems/first-missing-positive)
+| Challenge                                                                                                        | Level  | Java                                                                      | Kotlin                                                            |
+|------------------------------------------------------------------------------------------------------------------|--------|---------------------------------------------------------------------------|-------------------------------------------------------------------|
+| [20. ValidParentheses](https://leetcode.com/problems/valid-parentheses)                                          | 🔥     | [Solution](src/com/nphausg/leetcode/easy/ValidParentheses.java)           | -                                                                 |
+| [26. Remove Duplicates](https://leetcode.com/problems/remove-duplicates-from-sorted-array)                       | 🔥     | [Solution](src/com/nphausg/leetcode/easy/RemoveDuplicates.java)           | -                                                                 |
+| [27. Remove Element](https://leetcode.com/problems/remove-element)                                               | 🔥     | [Solution](src/com/nphausg/leetcode/easy/RemoveElement.java)              | -                                                                 |
+| [1929. Concatenation Of Array](https://leetcode.com/problems/concatenation-of-array)                             | 🔥     | [Solution](src/com/nphausg/leetcode/easy/ConcatenationArray.java)         | -                                                                 |
+| [17. Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number) | 🔥🔥   | [Solution](src/com/nphausg/leetcode/medium/LetterCombinations.java)       | -                                                                 |
+| [91. Decode Ways ](https://leetcode.com/problems/decode-ways)                                                    | 🔥🔥   | [Solution](src/com/nphausg/leetcode/medium/DecodeWays.java)               | -                                                                 |
+| [1143. Longest Common Subsequence](https://leetcode.com/problems/longest-common-subsequence)                     | 🔥🔥   | [Solution](src/com/nphausg/leetcode/medium/LongestCommonSubsequence.java) |
+| [658. Find K Closest Elements](https://leetcode.com/problems/find-k-closest-elements)                            | 🔥🔥   | [Solution](src/com/nphausg/leetcode/medium/FindClosestElements.java)      | -                                                                 |
+| [41. First Missing Positive](https://leetcode.com/problems/first-missing-positive)                               | 🔥🔥🔥 | [Solution](src/com/nphausg/leetcode/hard/FirstMissingPositive.java)       | [Solution](src/com/nphausg/leetcode/hard/FirstMissingPositive.kt) |
 
 ![-----------------------------------------------------](https://raw.githubusercontent.com/andreasbm/readme/master/assets/lines/colored.png)
 
 ## 👇 Author
 
 <p>
     <a href="https://nphausg.medium.com/" target="_blank">
-    <img src="https://avatars2.githubusercontent.com/u/13111806?s=400&u=f09b6160dbbe2b7eeae0aeb0ab4efac0caad57d7&v=4" width="96" height="96">
+    <img src="https://avatars2.githubusercontent.com/u/13111806?s=400&u=f09b6160dbbe2b7eeae0aeb0ab4efac0caad57d7&v=4" width="96" height="96" alt="">
     </a>
 </p>

.idea/kotlinc.xml

@@ -0,0 +1,28 @@
+/**
+ * Created by nphau on 09/12/2021, 00:30
+ * Copyright (c) 2021 . All rights reserved.
+ * Last modified 09/12/2021, 15:54
+ */
+package com.nphausg.leetcode;
+
+import com.nphausg.leetcode.medium.LongestCommonSubsequence;
+
+public class Main {
+
+    public static void main(String[] args) {
+
+        // Test 1: 3
+        String text1 = "abcde";
+        String text2 = "ace";
+
+        // Test 2: 3
+        // String text1 = "abc";
+        // String text2 = "abc";
+
+        // Test 3: 0
+        // String text1 = "abc";
+        // String text2 = "def";
+
+        System.out.println(LongestCommonSubsequence.longestCommonSubsequence(text1, text2));
+    }
+}

.idea/libraries/KotlinJavaRuntime.xml

@@ -3,14 +3,14 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.easy;
+package com.nphausg.leetcode.easy;
 
 /**
  * Given an integer array nums of length n, you want to create an array ans of length 2n
  * where ans[i] == nums[i] and ans[i + n] == nums[i] for 0 <= i < n (0-indexed).
  * Specifically, ans is the concatenation of two nums arrays.
  * Return the array ans.
- * https://leetcode.com/problems/concatenation-of-array/
+ * <a href="https://leetcode.com/problems/concatenation-of-array/">...</a>
  */
 public class ConcatenationArray {
 

README.md

@@ -6,7 +6,7 @@
  * https://leetcode.com/problems/remove-duplicates-from-sorted-array/
  * </p>
  */
-package sg.nphau.leetcode.easy;
+package com.nphausg.leetcode.easy;
 
 public class RemoveDuplicates {
     public int removeDuplicates(int[] nums) {

out/production/leetcode.solution/META-INF/leetcode.solution.kotlin_module

@@ -3,10 +3,10 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.easy;
+package com.nphausg.leetcode.easy;
 
 /**
- * https://leetcode.com/problems/remove-element/
+ * <a href="https://leetcode.com/problems/remove-element/">...</a>
  */
 public class RemoveElement {
 

src/com/.DS_Store

@@ -3,12 +3,12 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.easy;
+package com.nphausg.leetcode.easy;
 
 import java.util.Stack;
 
 /**
- * https://leetcode.com/problems/valid-parentheses
+ * <a href="https://leetcode.com/problems/valid-parentheses">...</a>
  */
 public class ValidParentheses {
     public boolean isValid(String s) {

src/com/nphausg/leetcode/Main.java

@@ -3,7 +3,7 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.hard;
+package com.nphausg.leetcode.hard;
 
 import java.util.Arrays;
 

src/sg/nphau/leetcode/easy/ConcatenationArray.java renamed to src/com/nphausg/leetcode/easy/ConcatenationArray.java

@@ -4,10 +4,11 @@
  * Last modified 09/12/2021, 15:54
  */
 
-package sg.nphau.leetcode.medium;
+package com.nphausg.leetcode.medium;
 
 /**
- * https://leetcode.com/problems/decode-ways/
+ * 91. Decode Ways
+ * <a href="https://leetcode.com/problems/decode-ways/">...</a>
  */
 public class DecodeWays {
 

src/sg/nphau/leetcode/easy/RemoveDuplicates.java renamed to src/com/nphausg/leetcode/easy/RemoveDuplicates.java

@@ -3,16 +3,17 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.medium;
+package com.nphausg.leetcode.medium;
 
 import java.util.ArrayList;
 import java.util.List;
 
 /**
- * https://leetcode.com/problems/find-k-closest-elements/
+ * 658. Find K Closest Elements
+ * <a href="https://leetcode.com/problems/find-k-closest-elements/">...</a>
  */
 public class FindClosestElements {
-    public List<Integer> findClosestElements(int[] arr, int k, int x) {
+    public static List<Integer> findClosestElements(int[] arr, int k, int x) {
         int left = 0, right = arr.length - k;
         while (left < right) {
             int mid = left + (right - left) / 2;

src/sg/nphau/leetcode/easy/RemoveElement.java renamed to src/com/nphausg/leetcode/easy/RemoveElement.java

@@ -3,14 +3,15 @@
  * Copyright (c) 2021 . All rights reserved.
  * Last modified 09/12/2021, 15:54
  */
-package sg.nphau.leetcode.medium;
+package com.nphausg.leetcode.medium;
 
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
 /**
- * https://leetcode.com/problems/letter-combinations-of-a-phone-number
+ * 17. Letter Combinations of a Phone Number
+ * <a href="https://leetcode.com/problems/letter-combinations-of-a-phone-number">...</a>
  */
 public class LetterCombinations {
     public List<String> letterCombinations(String digits) {

src/sg/nphau/leetcode/easy/ValidParentheses.java renamed to src/com/nphausg/leetcode/easy/ValidParentheses.java

@@ -0,0 +1,36 @@
+package com.nphausg.leetcode.medium;
+
+/**
+ * 1143. Longest Common Subsequence
+ * The longest common subsequence problem is a classic dynamic programming problem.
+ * The approach involves breaking down the problem into smaller subproblems and building up the solution using a DP table.
+ * This method ensures that we efficiently compute the length of the longest common subsequence in
+ * 𝑂(𝑚×𝑛) time.
+ * <a href="https://leetcode.com/problems/longest-common-subsequence">...</a>
+ */
+public class LongestCommonSubsequence {
+
+    public static int longestCommonSubsequence(String text1, String text2) {
+        if (text1.isEmpty() || text2.isEmpty()) {
+            return 0;
+        }
+
+        int m = text1.length();
+        int n = text2.length();
+
+        // Create a 2D array to store the lengths of LCS
+        int[][] dp = new int[m + 1][n + 1];
+
+        for (int i = 1; i <= m; i++) {
+            for (int j = 1; j <= n; j++) {
+                if (text1.charAt(i - 1) == text2.charAt(j - 1)) {
+                    dp[i][j] = dp[i - 1][j - 1] + 1;
+                } else {
+                    dp[i][j] = Math.max(dp[i - 1][j], dp[i][j - 1]);
+                }
+            }
+        }
+        // The length of the longest common subsequence
+        return dp[m][n];
+    }
+}