longest common subsequence

Author: dheeraj9198

src/BinaryTree/PrintPostFromPreInOrder.java

@@ -23,14 +23,14 @@ private void start() {
     }
 
     private void buildTree(int start, int end) {
-        if (start > end ) {
+        if (start > end) {
             return;
         }
         int data = preorder[preIndex++];
         int pos = findPos(data);
         buildTree(start, pos - 1);
         buildTree(pos + 1, end);
-            System.out.print(data+" ");
+        System.out.print(data + " ");
     }
 
     private int findPos(int data) {

src/DP/LcS.java

@@ -0,0 +1,55 @@
+package DP;
+
+import java.util.Stack;
+
+/**
+ * Created by dheeraj on 7/9/2016.
+ */
+public class LCS {
+
+    private static Integer sol[][];
+
+    private static int findLis(String one, String two, int start, int end) {
+        if(start < 0 || start > one.length()-1 || end > two.length()-1 || end <  0){
+            return 0;
+        }
+        if (sol[start][end] != null) {
+            return sol[start][end];
+        }
+        int a = findLis(one, two, start - 1, end - 1);
+        int b = findLis(one, two, start - 1, end);
+        int c = findLis(one, two, start, end - 1);
+
+        int ans = one.charAt(start) == two.charAt(end) ? a + 1 : Math.max(b, c);
+        sol[start][end] = ans;
+        return ans;
+    }
+
+    public static void main(String[] strings) {
+        String one = "abcd";
+        String two = "abcxd";
+
+        sol = new Integer[one.length()][two.length()];
+        int ans = findLis(one, two, one.length() - 1, two.length() - 1);
+        System.out.println(ans);
+
+        Stack<Character> characters = new Stack<Character>();
+        int x = one.length()-1;
+        int y = two.length()-1;
+        while(x >= 0 && y >=0){
+
+            if(x-1 >= 0 && sol[x][y] == sol[x-1][y]){
+                x--;
+            }else if(y-1 > 0 && sol[x][y] == sol[x][y-1]){
+                y--;
+            }else{
+                characters.push(one.charAt(x));
+                x--;y--;
+            }
+        }
+        while(!characters.empty()){
+            System.out.print(characters.pop()+" ");
+        }
+    }
+
+}

src/heap/KMostFrequent.java

@@ -6,9 +6,9 @@
  * Created by dheeraj on 7/8/2016.
  */
 public class KMostFrequent {
-
-    static Data[] datas = new Data[4];
-    static int size;
+    private static HashMap<String, Data> wordCountMap = new HashMap<String, Data>();
+    private static Data[] datas = new Data[4];
+    private static int size;
 
     private static void addToHeap(Data data) {
         if (size < datas.length) {
@@ -91,8 +91,6 @@ public String toString() {
         }
     }
 
-    private static HashMap<String, Data> wordCountMap = new HashMap<String, Data>();
-
     private static void addWord(String word) {
         Data data = wordCountMap.get(word);
         if (data == null) {