callbacks.js

const firstItem = (arr, cb) => {
  // firstItem passes the first item of the given array to the callback function.
  const name = arr[0];
  cb(name);
};

const getLength = (arr, cb) => {
  // getLength passes the length of the array into the callback.
  cb(arr.length);
};

const last = (arr, cb) => {
  // last passes the last item of the array into the callback.
  cb(arr[arr.length - 1]);
};

const sumNums = (x, y, cb) => {
  // sumNums adds two numbers (x, y) and passes the result to the callback.
  let sums = (x + y);
  cb(sums)
};


const multiplyNums = (x, y, cb) => {
  // multiplyNums multiplies two numbers and passes the result to the callback.
  let product = (x*y);
  cb(product)
};

const contains = (item, list, cb) => {
  // contains checks if an item is present inside of the given array/list.
  // Pass true to the callback if it is, otherwise pass false.
  for(let i = 0;) i < list.length; i++ {
 if(item = item)
 return true 
 }
 cb(item)
};

/* STRETCH PROBLEM */

const removeDuplicates = (array, cb) => {
  // removeDuplicates removes all duplicate values from the given array.
  // Pass the duplicate free array to the callback function.
  // Do not mutate the original array.
  const newArr = [];
   for (let i = 0; i < array.length; i++) {
     if ( newArr.indexOf(array[i]) === -1) {
       newArr.push(array[i]);
     }
   }
  cb(newArr);






};

/* eslint-enable */
module.exports = {
  firstItem,
  getLength,
  last,
  sumNums,
  multiplyNums,
  contains,
  removeDuplicates
};