text: const LinkedListStack = require('./LinkedListStack');
  const ArrayStack = require('./ArrayStack');
  
  function testStack (stack, opCount) {
    const startTime = new Date().getTime();
  
  
    for (let i = 0; i < opCount; i++) {
      let random = parseInt(Math.random() * 1000);
      stack.push(random);
    }
    for (let i = 0; i < opCount; i++) {
      stack.pop();
    }
    const endTime = new Date().getTime();
  
    return (endTime - startTime) / 1000;
  }
  
  function test() {
    const optCount = 100000;
  
    const arrayStack = new ArrayStack();
    const time1 = testStack(arrayStack, optCount);
    console.log(time1);
  
    const linkedStack = new LinkedListStack();
    const time2 = testStack(linkedStack, optCount);
    console.log(time2);
  }
  
  test()
  