Design a Min Stack

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. Implement the MinStack class: MinStack() initializes the stack object. void push(int val) pushes the element val onto the stack. void pop() removes the element on the top of the stack. int top() gets the top element of the stack. int getMin() retrieves the minimum element in the stack. Constraints: Calls to all functions are less than or equal to 3 * 10^4. -2^31 <= val <= 2^31 - 1 Test cases: push(3), push(5), getMin(), pop(), top() push(2), push(1), getMin(), pop(), getMin() Example Input push(3) push(5) getMin() pop() top()