Done design-2

Exercise_1.py

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+# Queues using the stack
+
+#Time complexity O(1) for each operation, SpaceComplexity O(n) where n is the number of elemnts present
+# Used 2 stacks, when input is coming keep loadin in satck 1, when popnor peek is called it is removed from stack 2
+# stack 2 is filled when it is empty, all the elemnts from the stack 1 is moved to stack to such that top element in
+# stack 2 move to bottom on stack 1, giving us FIFO when removing elemnts from stack 2
+
+class MyQueue:
+
+    def __init__(self):
+        self.enteringStack = []
+        self.outgoingStack = []
+
+    def push(self, x: int) -> None:
+        self.enteringStack.append(x)
+
+    def pop(self) -> int:
+        self.readjustStacksIfNeeded()
+        return self.outgoingStack.pop()
+
+    def peek(self) -> int:
+        self.readjustStacksIfNeeded()
+        return self.outgoingStack[-1]
+
+    def empty(self) -> bool:
+        return (len(self.enteringStack) + len(self.outgoingStack)) == 0 
+
+    def readjustStacksIfNeeded(self):
+        #Because of the constraint pop and ppek are valid, no need to check if enteringStack is empty
+        #reload the outgoingStack if enteringStack is not empty
+        if len(self.outgoingStack) == 0:
+            while len (self.enteringStack) > 0:
+                self.outgoingStack.append(self.enteringStack.pop())
+
+
+# Your MyQueue object will be instantiated and called as such:
+# obj = MyQueue()
+# obj.push(x)
+# param_2 = obj.pop()
+# param_3 = obj.peek()
+# param_4 = obj.empty()

Exercise_2.py

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+class MyHashMap:
+
+    def __init__(self):
+        self.primaryArray = [None]*1001
+
+    def put(self, key: int, value: int) -> None:
+        primaryHash = self.primaryHash(key)
+        if self.primaryArray[primaryHash] == None:
+            # since we have to return -1 if key doesn't exist, creating the array initialized to -1
+            # this will automatically return -1 for keys that are not present
+            self.primaryArray[primaryHash] = [-1]*1000
+
+        secondarHash = self.secondaryHash(key)
+        self.primaryArray[primaryHash][secondarHash] = value
+
+    def get(self, key: int) -> int:
+        primaryHash = self.primaryHash(key)
+        if self.primaryArray[primaryHash] == None:
+            return -1
+        else:
+            secondaryHash = self.secondaryHash(key)
+            return self.primaryArray[primaryHash][secondaryHash]
+
+    def remove(self, key: int) -> None:
+        primaryHash = self.primaryHash(key)
+        if self.primaryArray[primaryHash] == None:
+            return
+        else:
+            secondaryHash = self.secondaryHash(key)
+            self.primaryArray[primaryHash][secondaryHash] = -1
+
+    def primaryHash(self, key):
+        return key//1000
+
+    def secondaryHash(self,key):
+        return key%1000
+
+
+
+
+# Your MyHashMap object will be instantiated and called as such:
+# obj = MyHashMap()
+# obj.put(key,value)
+# param_2 = obj.get(key)
+# obj.remove(key)