class MinStack {

constructor() {

this.elements = [];

this.mins = [];

this.min = undefined;

}

push(element) {

this.elements.push(element);

if (element < this.min || this.min === undefined) {

this.min = element;

this.mins.push(element);

}

}

pop() {

if (this.elements.length > 0) {

const elementToPop = this.elements.pop();

if (elementToPop === this.min) {

this.mins.pop();

this.min = this.mins[this.mins.length - 1];

}

return elementToPop;

}

}

}

const myMinStack = new MinStack();

myMinStack.push(3);

myMinStack.push(4);

myMinStack.push(5);

myMinStack.push(1);

myMinStack.push(-100);

console.log(myMinStack.min);