Stand in Line i can't understanding this topic please anyone help me

Tell us what’s happening:

Your code so far


function nextInLine(arr, item) {
  // Your code here

  return item;  // Change this line
}

// Test Setup
var testArr = [1,2,3,4,5];

// Display Code
console.log("Before: " + JSON.stringify(testArr));

console.log(nextInLine(testArr,1)); 
console.log(nextInLine(testArr,2));
console.log(nextInLine(testArr,5));// Modify this line to test
console.log("After: " + JSON.stringify(testArr));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/stand-in-line

I’ll give you two hints…

.push()
.shift()