Merge pull request #151 from nishagii/feature/longes-common-subsequence-java

PR : DP problem Longest Common Subsequence in Java

Author: admirerr

Java/dynamic-programming/LongestCommonSubsequence.java

@@ -0,0 +1,26 @@
+public class LongestCommonSubsequence {
+    public static void main(String[] args) {
+        String str1 = "AGGTAB";
+        String str2 = "GXTXAYB";
+        System.out.println("Length of Longest Common Subsequence between \"" + str1 + "\" and \"" + str2 + "\" is: " + lcs(str1, str2));
+    }
+
+    public static int lcs(String str1, String str2) {
+        int m = str1.length();
+        int n = str2.length();
+        int[][] dp = new int[m + 1][n + 1];
+
+        for (int i = 0; i <= m; i++) {
+            for (int j = 0; j <= n; j++) {
+                if (i == 0 || j == 0) {
+                    dp[i][j] = 0; // Base case: one string is empty
+                } else if (str1.charAt(i - 1) == str2.charAt(j - 1)) {
+                    dp[i][j] = dp[i - 1][j - 1] + 1; // Characters match
+                } else {
+                    dp[i][j] = Math.max(dp[i - 1][j], dp[i][j - 1]); // Characters don't match
+                }
+            }
+        }
+        return dp[m][n];
+    }
+}