Done Design-1

Sample.java

@@ -1,7 +1,113 @@
-// Time Complexity :
-// Space Complexity :
-// Did this code successfully run on Leetcode :
-// Any problem you faced while coding this :
+//Problem-1 Hashset
+// Time Complexity : O(1) for adding, deleting, contains
+// Space Complexity : 
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this : Getting partial testcases correct for assigning 1 extra bucket for 
+// secondary hash function. So added 1001 buckets in the global declaration of secondary buckets.
 
 
+class MyHashSet {
+    int primaryList;
+    int secondaryList;
+    boolean [][] storage;
+    public MyHashSet() {
+        this.primaryList=1000;
+        this.secondaryList=1001;
+        this.storage = new boolean[primaryList][];
+    }
+    private int primaryhash(int key)
+    {
+        return key % primaryList;
+    }
+    private int secondaryhash(int key)
+    {
+        return key / secondaryList;
+    }
+    public void add(int key) {
+        int primarykey= primaryhash(key);
+        if(storage[primarykey]==null)
+        {
+
+            storage[primarykey]= new boolean[secondaryList+1];
+        }
+        int secondarykey=secondaryhash(key);
+        storage[primarykey][secondarykey]=true;
+
+    }
+
+    public void remove(int key) {
+        int primarykey= primaryhash(key);
+        if(storage[primarykey]==null)
+        {
+            return;
+        }
+        else
+        {
+            int secondarykey=secondaryhash(key);
+            storage[primarykey][secondarykey]=false;
+        }
+
+    }
+
+    public boolean contains(int key) {
+        int primarykey= primaryhash(key);
+        if(storage[primarykey]==null)
+        {
+            return false;
+        }
+        else
+        {
+            int secondarykey=secondaryhash(key);
+            return storage[primarykey][secondarykey];
+        }
+
+    }
+}
+
+// Uses double hashing with primary hashing using a modulous and secondary hashing using a division operation.
+// took 1000 buckets in each hashing by Sq. root of 10^6.
+// used boolean instead of integers.
+
 // Your code here along with comments explaining your approach
+
+
+//Problem-2 Min Stack
+// Time Complexity : O(1) for push, pop as operations on stack is O(1)
+// Space Complexity : 
+// Did this code successfully run on Leetcode : yes
+// Any problem you faced while coding this : 
+
+class MinStack {
+    Stack<Integer> stack;
+    Stack<Integer> minStack;
+    int min;
+    public MinStack() {
+        this.stack = new Stack<>();
+        this.minStack = new Stack<>();
+        min=Integer.MAX_VALUE;
+        minStack.push(min);
+    }
+
+    public void push(int val) {
+        min=Math.min(val,min);
+        stack.push(val);
+        minStack.push(min);
+    }
+
+    public void pop() {
+        stack.pop();
+        minStack.pop();
+        min=minStack.peek();
+
+    }
+
+    public int top() {
+        return stack.peek();
+    }
+
+    public int getMin() {
+        return min;
+    }
+}
+
+