Merge pull request #140 from tadiharshith/main

Array.java

DSA/Search/Array.java

@@ -0,0 +1,27 @@
+
+class GFG {
+	public static void main(String[] args)
+	{
+
+		int[] arr;
+
+
+		arr = new int[5];
+
+
+		arr[0] = 10;
+
+
+		arr[1] = 20;
+
+		// so on...
+		arr[2] = 30;
+		arr[3] = 40;
+		arr[4] = 50;
+
+
+		for (int i = 0; i < arr.length; i++)
+			System.out.println("Element at index " + i
+							+ " : " + arr[i]);
+	}
+}

DSA/Search/Graph.java

@@ -0,0 +1,130 @@
+
+
+import java.util.*;
+
+class Graph<T> {
+
+
+	private Map<T, List<T> > map = new HashMap<>();
+
+
+	public void addVertex(T s)
+	{
+		map.put(s, new LinkedList<T>());
+	}
+
+	public void addEdge(T source,
+						T destination,
+						boolean bidirectional)
+	{
+
+		if (!map.containsKey(source))
+			addVertex(source);
+
+		if (!map.containsKey(destination))
+			addVertex(destination);
+
+		map.get(source).add(destination);
+		if (bidirectional == true) {
+			map.get(destination).add(source);
+		}
+	}
+
+
+	public void getVertexCount()
+	{
+		System.out.println("The graph has "
+						+ map.keySet().size()
+						+ " vertex");
+	}
+
+
+	public void getEdgesCount(boolean bidirection)
+	{
+		int count = 0;
+		for (T v : map.keySet()) {
+			count += map.get(v).size();
+		}
+		if (bidirection == true) {
+			count = count / 2;
+		}
+		System.out.println("The graph has "
+						+ count
+						+ " edges.");
+	}
+
+	public void hasVertex(T s)
+	{
+		if (map.containsKey(s)) {
+			System.out.println("The graph contains "
+							+ s + " as a vertex.");
+		}
+		else {
+			System.out.println("The graph does not contain "
+							+ s + " as a vertex.");
+		}
+	}
+
+
+	public void hasEdge(T s, T d)
+	{
+		if (map.get(s).contains(d)) {
+			System.out.println("The graph has an edge between "
+							+ s + " and " + d + ".");
+		}
+		else {
+			System.out.println("The graph has no edge between "
+							+ s + " and " + d + ".");
+		}
+	}
+
+	public String toString()
+	{
+		StringBuilder builder = new StringBuilder();
+
+		for (T v : map.keySet()) {
+			builder.append(v.toString() + ": ");
+			for (T w : map.get(v)) {
+				builder.append(w.toString() + " ");
+			}
+			builder.append("\n");
+		}
+
+		return (builder.toString());
+	}
+}
+
+
+public class Main {
+
+	public static void main(String args[])
+	{
+
+
+		Graph<Integer> g = new Graph<Integer>();
+
+		g.addEdge(0, 1, true);
+		g.addEdge(0, 4, true);
+		g.addEdge(1, 2, true);
+		g.addEdge(1, 3, true);
+		g.addEdge(1, 4, true);
+		g.addEdge(2, 3, true);
+		g.addEdge(3, 4, true);
+
+
+		System.out.println("Graph:\n"
+						+ g.toString());
+
+
+		g.getVertexCount();
+
+
+		g.getEdgesCount(true);
+
+
+		g.hasEdge(3, 4);
+
+
+		g.hasVertex(5);
+	}
+}

DSA/Search/Linkedlist.java

@@ -0,0 +1,77 @@
+import java.io.*;
+public class LinkedList {
+
+	Node head; // head of list
+
+	static class Node {
+
+		int data;
+		Node next;
+
+
+		Node(int d)
+		{
+			data = d;
+			next = null;
+		}
+	}
+
+
+	public static LinkedList insert(LinkedList list, int data)
+	{
+
+		Node new_node = new Node(data);
+
+
+		if (list.head == null) {
+			list.head = new_node;
+		}
+		else {
+			Node last = list.head;
+			while (last.next != null) {
+				last = last.next;
+			}
+
+
+			last.next = new_node;
+		}
+
+
+		return list;
+	}
+
+
+	public static void printList(LinkedList list)
+	{
+		Node currNode = list.head;
+
+		System.out.print("LinkedList: ");
+		while (currNode != null) {
+
+			System.out.print(currNode.data + " ");
+
+			// Go to next node
+			currNode = currNode.next;
+		}
+	}
+
+
+	public static void main(String[] args)
+	{
+
+		LinkedList list = new LinkedList();
+
+		list = insert(list, 1);
+		list = insert(list, 2);
+		list = insert(list, 3);
+		list = insert(list, 4);
+		list = insert(list, 5);
+		list = insert(list, 6);
+		list = insert(list, 7);
+		list = insert(list, 8);
+
+
+
+		printList(list);
+	}
+}

DSA/Search/Queue.java

@@ -0,0 +1,36 @@
+
+
+import java.util.LinkedList;
+import java.util.Queue;
+
+public class QueueExample {
+
+	public static void main(String[] args)
+	{
+		Queue<Integer> q
+			= new LinkedList<>();
+
+		for (int i = 0; i < 5; i++)
+			q.add(i);
+
+
+		System.out.println("Elements of queue "
+						+ q);
+
+
+		int removedele = q.remove();
+		System.out.println("removed element-"
+						+ removedele);
+
+		System.out.println(q);
+
+
+		int head = q.peek();
+		System.out.println("head of queue-"
+						+ head);
+
+		int size = q.size();
+		System.out.println("Size of queue-"
+						+ size);
+	}
+}

DSA/Search/circularll.java

@@ -0,0 +1,26 @@
+
+static Node addAfter(Node last, int data, int item)
+{
+	if (last == null)
+		return null;
+
+	Node temp, p;
+	p = last.next;
+	do {
+		if (p.data == item) {
+			temp = new Node();
+			temp.data = data;
+			temp.next = p.next;
+			p.next = temp;
+
+			if (p == last)
+				last = temp;
+			return last;
+		}
+		p = p.next;
+	} while (p != last.next);
+
+	System.out.println(item + " not present in the list.");
+	return last;
+}
+