Added code to find longest common subsequence

Dynamic Programming/longestcommonsubsequence.java

@@ -0,0 +1,34 @@
+import java.io.*;
+import java.util.*;
+
+public class longestcommonsubsequence 
+{
+    public static int find(char[] arr,char[] brr,int n,int m)
+    {
+        int[][] dp = new int[n+1][m+1];
+        for(int i=0;i<=n;i++)
+        {
+            for(int j=0;j<=m;j++)
+            {
+                if(i == 0 || j == 0)
+                    dp[i][j] = 0;
+                else if(arr[i-1] == brr[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]);
+            }
+        }
+        return dp[n][m];
+    }
+    public static void main(String[] args) throws Exception 
+    {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        String str = br.readLine();
+        String str1 = br.readLine();
+        char[] arr = str.toCharArray();
+        char[] brr = str1.toCharArray();
+        int n = str.length();
+        int m = str1.length();
+        System.out.println("Length of the maximum common subsequence : " + find(arr,brr,n,m));
+    }
+}