Merge pull request #426 from rpjayasekara/heapSort-java

Heap sort java

Dynamic Programming/sub set sum/python/subSetSum.py

@@ -0,0 +1,28 @@
+def isSubsetSum(set,n, sum) : 
+
+    # Base Cases 
+    if (sum == 0) : 
+        return True
+    if (n == 0 and sum != 0) : 
+        return False
+
+    # If last element is greater than 
+    # sum, then ignore it 
+    if (set[n - 1] > sum) : 
+        return isSubsetSum(set, n - 1, sum)
+
+    # else, check if sum can be obtained 
+    # by any of the following 
+    # (a) including the last element 
+    # (b) excluding the last element    
+    return isSubsetSum(set, n-1, sum) or isSubsetSum(set, n-1, sum-set[n-1]) 
+
+
+# Test case
+set = [3, 34, 4, 12, 5, 2] 
+sum = 100
+n = len(set) 
+if (isSubsetSum(set, n, sum) == True) : 
+    print("Found a subset with given sum") 
+else : 
+    print("No subset with given sum") 

Graphs/BinaryTree/java/binaryTree.java

@@ -0,0 +1,82 @@
+class BinarySearchTree { 
+
+    /* Class containing left and right child of current node and key value*/
+    class Node { 
+        int key; 
+        Node left, right; 
+
+        public Node(int item) { 
+            key = item; 
+            left = right = null; 
+        } 
+    } 
+
+    // Root of BST 
+    Node root; 
+
+    // Constructor 
+    BinarySearchTree() {  
+        root = null;  
+    } 
+
+    // This method mainly calls insertRec() 
+    void insert(int key) { 
+       root = insertRec(root, key); 
+    } 
+
+    /* A recursive function to insert a new key in BST */
+    Node insertRec(Node root, int key) { 
+
+        /* If the tree is empty, return a new node */
+        if (root == null) { 
+            root = new Node(key); 
+            return root; 
+        } 
+
+        /* Otherwise, recur down the tree */
+        if (key < root.key) 
+            root.left = insertRec(root.left, key); 
+        else if (key > root.key) 
+            root.right = insertRec(root.right, key); 
+
+        /* return the (unchanged) node pointer */
+        return root; 
+    } 
+
+    // This method mainly calls InorderRec() 
+    void inorder()  { 
+       inorderRec(root); 
+    } 
+
+    // A utility function to do inorder traversal of BST 
+    void inorderRec(Node root) { 
+        if (root != null) { 
+            inorderRec(root.left); 
+            System.out.println(root.key); 
+            inorderRec(root.right); 
+        } 
+    } 
+
+    // Driver Program to test above functions 
+    public static void main(String[] args) { 
+        BinarySearchTree tree = new BinarySearchTree(); 
+
+        /* Let us create following BST 
+              50 
+           /     \ 
+          30      70 
+         /  \    /  \ 
+       20   40  60   80 */
+        tree.insert(50); 
+        tree.insert(30); 
+        tree.insert(20); 
+        tree.insert(40); 
+        tree.insert(70); 
+        tree.insert(60); 
+        tree.insert(80); 
+
+        // print inorder traversal of the BST 
+        tree.inorder(); 
+    } 
+} 
+// This code is contributed by Ankur Narain Verma 

Graphs/BinaryTree/python/binaryTree.py

@@ -0,0 +1,64 @@
+#Class which represents a node of binary tree
+class Node:
+    def __init__(self,key): 
+        self.left = None
+        self.right = None
+        self.val = key 
+
+#Function which add a key to binary tree
+def insert(root,node): 
+    if root is None: 
+        root = node 
+    else: 
+        if root.val < node.val: 
+            if root.right is None: 
+                root.right = node 
+            else: 
+                insert(root.right, node) 
+        else: 
+            if root.left is None: 
+                root.left = node 
+            else: 
+                insert(root.left, node) 
+#Function to do inorder tree traversal
+def inorder(root): 
+    if root: 
+        inorder(root.left) 
+        print(root.val) 
+        inorder(root.right) 
+
+#Function for searching a key in the tree
+def search(root,key): 
+
+    # Base Cases: root is null or key is present at root 
+    if root is None: 
+        return False
+    elif root.val == key:
+        return True 
+
+    # Key is greater than root's key 
+    if root.val < key: 
+        return search(root.right,key) 
+
+    # Key is smaller than root's key 
+    return search(root.left,key) 
+
+
+#Test case
+
+r = Node(50) 
+insert(r,Node(30)) 
+insert(r,Node(20)) 
+insert(r,Node(40)) 
+insert(r,Node(70)) 
+insert(r,Node(60)) 
+insert(r,Node(80)) 
+
+print "Result of traversing"
+inorder(r) 
+
+
+print "Is 25 in the tree?", search(r,25)
+print "Is 30 in the tree?", search(r,30)
+print "Is 2 in the tree?", search(r,2)
+

Searching/Linear Search/java/linearSearch.java

@@ -0,0 +1,17 @@
+class LinearSearch 
+{ 
+    // This function returns index of element x in arr[] 
+    static int search(int arr[], int n, int x) 
+    { 
+        for (int i = 0; i < n; i++) 
+        { 
+            // Return the index of the element if the element 
+            // is found 
+            if (arr[i] == x) 
+                return i; 
+        } 
+
+        // return -1 if the element is not found 
+        return -1; 
+    } 
+}  

data structures/stack/java/stack.java

@@ -0,0 +1,57 @@
+import java.io.*; 
+import java.util.*; 
+
+class Test 
+{    
+    // Pushing element on the top of the stack 
+    static void stack_push(Stack<Integer> stack) 
+    { 
+        for(int i = 0; i < 5; i++) 
+        { 
+            stack.push(i); 
+        } 
+    } 
+
+    // Popping element from the top of the stack 
+    static void stack_pop(Stack<Integer> stack) 
+    { 
+        System.out.println("Pop :"); 
+
+        for(int i = 0; i < 5; i++) 
+        { 
+            Integer y = (Integer) stack.pop(); 
+            System.out.println(y); 
+        } 
+    } 
+
+    // Displaying element on the top of the stack 
+    static void stack_peek(Stack<Integer> stack) 
+    { 
+        Integer element = (Integer) stack.peek(); 
+        System.out.println("Element on stack top : " + element); 
+    } 
+
+    // Searching element in the stack 
+    static void stack_search(Stack<Integer> stack, int element) 
+    { 
+        Integer pos = (Integer) stack.search(element); 
+
+        if(pos == -1) 
+            System.out.println("Element not found"); 
+        else
+            System.out.println("Element is found at position " + pos); 
+    } 
+
+
+    public static void main (String[] args) 
+    { 
+        Stack<Integer> stack = new Stack<Integer>(); 
+
+        stack_push(stack); 
+        stack_pop(stack); 
+        stack_push(stack); 
+        stack_peek(stack); 
+        stack_search(stack, 2); 
+        stack_search(stack, 6); 
+    } 
+}