update var to const in function declarations

calculator/calculator.js

@@ -1,26 +1,26 @@
-function add(a, b) {
+const add = function(a, b) {
   return a + b;
 }
 
-function subtract(a, b) {
+const subtract = function(a, b) {
   return a - b;
 }
 
-function sum(array) {
+const sum = function(array) {
   return array.reduce((total, current) => total + current, 0);
 }
 
-function multiply(array) {
+const multiply = function(array) {
     return array.length
       ? array.reduce((accumulator, nextItem) => accumulator * nextItem)
       : 0;
 }
 
-function power(a, b) {
+const power = function(a, b) {
   return Math.pow(a, b);
 }
 
-function factorial(n) {
+const factorial = function(n) {
   if (n == 0) return 1;
   let product = 1;
   for (let i = n; i > 0; i--) {
@@ -31,7 +31,7 @@ function factorial(n) {
 
 // This is another implementation of Factorial that uses recursion
 // THANKS to @ThirtyThreeB!
-function recursiveFactorial(n) {
+const recursiveFactorial = function(n) {
   if (n===0){
     return 1;
   }

getTheTitles/getTheTitles.js

@@ -1,4 +1,4 @@
-var getTheTitles = function(array) {
+const getTheTitles = function(array) {
   return array.map(book => book.title)
 }
 

helloWorld/helloWorld.js

@@ -1,4 +1,4 @@
-var helloWorld = function() {
+const helloWorld = function() {
   return 'Hello, World!'
 }
 

leapYears/leapYears.js

@@ -1,4 +1,4 @@
-var leapYears = function(year) {
+const leapYears = function(year) {
   return year % 4 === 0 && ( year % 100 !== 0 || year % 400 == 0)
 }
 

pigLatin/pigLatin.js

@@ -1,4 +1,4 @@
-function pigLatin(string) {
+const pigLatin = function(string) {
 	return string
 	  .split(" ")
 	  .map(word => {
@@ -10,7 +10,7 @@ function pigLatin(string) {
 	  .join(" ");
   }
   
-  function firstVowelIndex(string) {
+const firstVowelIndex = function(string) {
 	const vowels = string.match(/[aeiou]/g);
 	if (vowels[0] == "u" && string[string.indexOf(vowels[0]) - 1] == "q") {
 	  return string.indexOf(vowels[1]);

repeatString/repeatString.js

@@ -1,4 +1,4 @@
-var repeatString = function(word, times) {
+const repeatString = function(word, times) {
   if (times < 0) return 'ERROR'
   let string = ''
   for (let i = 0; i < times; i++) {

reverseString/reverseString.js

@@ -1,4 +1,4 @@
-var reverseString = function(string) {
+const reverseString = function(string) {
  return string.split('').reverse().join('') 
 }
 

tempConversion/tempConversion.js

@@ -1,8 +1,8 @@
-var ftoc = function(f) {
+const ftoc = function(f) {
  return Math.round((f - 32) * (5/9) * 10) / 10
 }
 
-var ctof = function(c) {
+const ctof = function(c) {
   return Math.round(((c * 9/5) + 32) * 10) / 10 
 }