Thinkful JS Arrays exercises

arrayEvery.js

// Array Ex 6
function makeList(item1, item2, item3) {
  return [item1,item2,item3];
}

// tests
function testMakeList() {
  var items = ["prime rib", "fried goat cheese salad", "fish tacos"];
  var result = makeList(items[0], items[1], items[2]);
  
  if (
    result && result.length && items.length === result.length &&
    items.every(function(item) {
      return result.indexOf(item) > -1;
    })) {
    console.log('SUCCESS: `makeList` works!');
  } else {
    console.error('FAILURE: `makeList` is not working');
  } 
}

testMakeList();

arrayExercises.js

// Arrays Ex 1
function accessFirstItem(array) {
  return array[0]
}

function accessThirdItem(array) {
  return array[2]
}

arrayFilter.js

// Arrays Ex 7
function shortWords(array) {
  return array.filter(function(str) {return str.length < 5});
}

arrayFind.js

// Arrays Ex 8
function divisibleBy5(array) {
  return array.find(function(num) {return num%5 === 0;})
}

arrayLength.js

// Array Ex 5
function findLength(array) {
  return array.length
}

function accessLastItem(array) {
  return array[array.length-1]
}

arrayMap.js

// Arrays Ex 10
function squares(array) {
  return array.map(function(num) {return num*num});
}

function squares(array) {
  var result = array.map(function(num) {
    return num**2;
  });
  return result;
}

arrayPush.js

// Arrays Ex 2
function addToList(list, item) {
  list.push(item)
  return list
}

arraySlice.js

// Arrays Ex 3
function firstFourItems(array) {
  return array.slice(0,4);
}

function lastThreeItems(array) {
  return array.slice(-3);
}

arraySlice2.js

// Array Ex 4
function minusLastItem(array) {
  return array.slice(0,-1);
}

function copyFirstHalf(array) {
  if {
    array.length % 2 === 0;
    return array.slice(0,array.length % 2));
  else {
    return array.slice()
  }
}

// Correct solution:
function copyFirstHalf(array) {
  return array.slice(0,array.length/2);
}

arraySort.js

// Arrays Ex 9
function greatestToLeast(array) {
  return array.sort(function(a,b) {return b-a;});
}