Design-1 solution

hashset.py

@@ -0,0 +1,64 @@
+# // Time Complexity : add, remove and contains operations are O(1) 
+# // Space Complexity : O(buckets * bucket_size) maximum space used when all the buckets are filled
+# // Did this code successfully run on Leetcode : Yes
+# // Any problem you faced while coding this : NA
+
+class MyHashSet(object):
+    buckets = 1000
+    bucket_size=1001
+
+    def __init__(self):
+        self.hashset=[None] * self.buckets
+
+    def hashfunc1(self,key):
+        return key % self.buckets
+
+    def hashfunc2(self,key):
+        return key // self.buckets
+
+    def add(self, key):
+        """
+        :type key: int
+        :rtype: None
+        """
+        primary_bucket = self.hashfunc1(key)
+        secondary_index = self.hashfunc2(key)
+        if self.hashset[primary_bucket] is None:
+            self.hashset[primary_bucket] = [False] * self.bucket_size
+
+        self.hashset[primary_bucket][secondary_index] = True
+
+
+    def remove(self, key):
+        """
+        :type key: int
+        :rtype: None
+        """
+
+        primary_bucket = self.hashfunc1(key)
+        secondary_index = self.hashfunc2(key)
+
+        if self.hashset[primary_bucket] is not None:
+            self.hashset[primary_bucket][secondary_index]=False  
+
+
+    def contains(self, key):
+        """
+        :type key: int
+        :rtype: bool
+        """
+        primary_bucket = self.hashfunc1(key)
+        secondary_index = self.hashfunc2(key)
+
+        if self.hashset[primary_bucket] is not None:
+            return self.hashset[primary_bucket][secondary_index]
+
+        return False 
+
+
+
+# Your MyHashSet object will be instantiated and called as such:
+# obj = MyHashSet()
+# obj.add(key)
+# obj.remove(key)
+# param_3 = obj.contains(key)

min-stack.py

@@ -0,0 +1,52 @@
+# // Time Complexity : all operations are O(1)
+# // Space Complexity : O(n)
+# // Did this code successfully run on Leetcode : Yes
+# // Any problem you faced while coding this : NA
+
+class MinStack(object):
+
+    def __init__(self):
+        self.stack=[]
+        self.minStack=[]
+
+    def push(self, val):
+        """
+        :type val: int
+        :rtype: None
+        """
+        self.stack.append(val)
+        if not self.minStack:
+            self.minStack.append(val)
+        else:
+            self.minStack.append(min(val,self.minStack[-1]))
+
+
+    def pop(self):
+        """
+        :rtype: None
+        """
+        self.stack.pop()
+        self.minStack.pop()
+
+
+    def top(self):
+        """
+        :rtype: int
+        """
+        return self.stack[-1]
+
+
+    def getMin(self):
+        """
+        :rtype: int
+        """
+        return self.minStack[-1]
+
+
+
+# Your MinStack object will be instantiated and called as such:
+# obj = MinStack()
+# obj.push(val)
+# obj.pop()
+# param_3 = obj.top()
+# param_4 = obj.getMin()