From ae0024a29b82b71443ce477826e68854d44a62cf Mon Sep 17 00:00:00 2001
From: Rajj <rshankarling@seattleu.edu>
Date: Wed, 23 Oct 2024 16:51:26 -0500
Subject: [PATCH] Completed Design-2

---
 MyHashMap.java | 107 +++++++++++++++++++++++++++++++++++++++++++++++++
 MyQueue.java   |  63 +++++++++++++++++++++++++++++
 2 files changed, 170 insertions(+)
 create mode 100644 MyHashMap.java
 create mode 100644 MyQueue.java

diff --git a/MyHashMap.java b/MyHashMap.java
new file mode 100644
index 00000000..a79bb3b5
--- /dev/null
+++ b/MyHashMap.java
@@ -0,0 +1,107 @@
+// Time Complexity :put: O(1)
+//                  get: O(1)
+//                  remove: O(1)
+// Space Complexity :put: O(1)
+//                   get: O(1)
+//                   remove: O(1)
+//                   constructor: O(n) (because we are creating storage array)
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this : nothing
+
+
+
+class MyHashMap {
+
+    class Node {
+        int key;
+        int value;
+        Node next;
+
+        Node(int key, int value){
+            this.key = key;
+            this.value = value;
+        }
+
+    }
+
+    Node[] storage;
+    int buckets;
+
+    public MyHashMap() {
+        this.buckets=10000;
+        this.storage = new Node[buckets];
+    }
+
+    private int getPrimaryHash(int key){
+        return key % buckets;
+    }
+
+    private Node getPrevNode(Node head, int key){
+        Node prev = null;
+        Node curr = head;
+
+        while(curr != null && curr.key != key){
+            prev = curr;
+            curr = prev.next;
+        }
+        return prev;
+    }
+
+    public void put(int key, int value) {
+        int pIndex = getPrimaryHash(key);
+        if(storage[pIndex] == null){
+            storage[pIndex] = new Node(-1,-1);
+        }
+        Node prev= getPrevNode(storage[pIndex], key);
+        if(prev.next == null){
+            prev.next = new Node(key , value);
+        } else {
+            prev.next.value = value;
+        }
+
+    }
+
+    public int get(int key) {
+        int pIndex = getPrimaryHash(key);
+        if(storage[pIndex] == null){
+            return -1;
+        }
+        Node prev = getPrevNode(storage[pIndex], key);
+        if(prev.next == null){
+            return -1;
+        } else {
+            return prev.next.value;
+        }
+    }
+
+    public void remove(int key) {
+        int pIndex = getPrimaryHash(key);
+        if(storage[pIndex]== null){
+            return;
+        }
+        Node prev = getPrevNode(storage[pIndex], key);
+        if(prev.next == null){
+            return;
+        } else {
+            Node temp = prev.next;
+            prev.next = temp.next;
+            temp = null;
+        }
+    }
+
+
+    public static void main(String args[])
+    {
+        MyHashMap obj = new MyHashMap();
+        obj.put(2,10);
+        obj.put(4,10);
+        obj.put(2,12);
+        obj.put(5,30);
+        obj.put(6,3000);
+        obj.put(7,4000);
+        obj.remove(4);
+        System.out.println("Value corresponding to key 6 is "+obj.get(6));
+
+    }
+}
+
diff --git a/MyQueue.java b/MyQueue.java
new file mode 100644
index 00000000..8f672ba3
--- /dev/null
+++ b/MyQueue.java
@@ -0,0 +1,63 @@
+// Time Complexity : empty: O(1)
+//                   push: O(1)
+//                   pop: O(1)
+//                   peek: O(1)
+// Space Complexity : empty: O(1)
+//                    push: O(1)
+//                    pop: O(1)
+//                    peek: O(1)
+//                    constructor: O(2n) because we're creating stacks
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this : nothing
+
+import java.util.Stack;
+
+class MyQueue {
+        Stack<Integer> inStk;
+        Stack<Integer> outStk;
+    public MyQueue() {
+        this.inStk= new Stack<>();
+        this.outStk= new Stack<>();
+    }
+
+    public void push(int x) {
+        inStk.push(x);
+    }
+
+    public int pop() {
+        if(empty()) return -1;
+        if(outStk.isEmpty()){
+            while(!inStk.isEmpty()){
+                outStk.push(inStk.pop());
+            }
+        }
+        return outStk.pop();
+    }
+
+    public int peek() {
+        if(outStk.isEmpty()){
+            while(!inStk.isEmpty()){
+                outStk.push(inStk.pop());
+            }
+        }
+        return outStk.peek();
+    }
+
+    public boolean empty() {
+        return inStk.isEmpty() && outStk.isEmpty();
+    }
+
+
+    public static void main(String args[])
+    {
+        MyQueue queue = new MyQueue();
+        queue.push(10);
+        queue.push(20);
+        queue.push(30);
+        queue.push(9);
+        queue.push(7);
+        queue.push(6);
+        System.out.println(queue.pop() + " Popped from stack");
+        System.out.println(queue.peek() + " is top element of the stack");
+    }
+}