Min Stack

Explore how to design and implement a Min Stack, a custom data structure that allows push, pop, and minimum retrieval operations all in O(1) time. This lesson guides you through building efficient stack methods while meeting constraints on input values and operation count, helping you master constant time data access and manipulation in Go.

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Statement

Design a custom stack, Min Stack, allowing us to push, pop, and retrieve the minimum value in constant time. Implement the following methods for Min Stack struct:

NewMinStack(): This initializes the Min Stack object.
Pop(): This removes and returns from the stack the value that was most recently pushed onto it.
Push(): This pushes the provided value onto the stack.
Min Number(): This returns the minimum value in the stack in $O(1)$ time.

Note: The time complexity of all the methods above should be $O(1)$ .

Constraints:

$-10^{4} \leq$ value $\leq 10^{4}$
The Pop() and Min Number() methods will always be called on non-empty stacks.
At most, $10^3$ calls will be made to Push(), Pop(), and Min Number().

Examples

usercode > min_stack.go

package main
// MinStack declaration
type MinStack struct {
	// write your code here
}
func NewMinStack() *MinStack {
  	// Replace this placeholder return statement with your code
	return new(MinStack)
}
// Pop removes and returns value from stack
func (m *MinStack) Pop() int {
  	// Replace this placeholder return statement with your code
	return -1
}
// Push pushes value into the stack
func (m *MinStack) Push(value int) {
	// write your code here
}
// MinNumber returns minimum value in O(1)
func (m *MinStack) MinNumber() int {
  	// Replace this placeholder return statement with your code
	return -1
}

Min Stack

Min Stack

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