Allen Hai - JavaScript-II

assignments/array-methods.js

@@ -56,28 +56,65 @@ const runners = [{"id":1,"first_name":"Charmain","last_name":"Seiler","email":"c
 // ==== Challenge 1: Use .forEach() ====
 // The event director needs both the first and last names of each runner for their running bibs.  Combine both the first and last names into a new array called fullName. 
 let fullName = [];
+
+runners.forEach(({first_name, last_name}) => {
+    fullName.push({
+        first_name,
+        last_name 
+    })
+})
+
 console.log(fullName);
 
 // ==== Challenge 2: Use .map() ====
 // The event director needs to have all the runner's first names converted to uppercase because the director BECAME DRUNK WITH POWER. Convert each first name into all caps and log the result
-let allCaps = [];
+let allCaps = fullName.map(({first_name, last_name}) => (
+    {
+        first_name: first_name.toUpperCase(),
+        last_name
+    }
+))
+
 console.log(allCaps); 
 
 // ==== Challenge 3: Use .filter() ====
 // The large shirts won't be available for the event due to an ordering issue.  Get a list of runners with large sized shirts so they can choose a different size. Return an array named largeShirts that contains information about the runners that have a shirt size of L and log the result
-let largeShirts = [];
+let largeShirts = runners.filter(({shirt_size}) => {
+    if (shirt_size === "L") return true
+})
 console.log(largeShirts);
 
 // ==== Challenge 4: Use .reduce() ====
 // The donations need to be tallied up and reported for tax purposes. Add up all the donations into a ticketPriceTotal array and log the result
-let ticketPriceTotal = [];
+let ticketPriceTotal = runners.reduce((accum, {donation} ) => (
+    accum + donation
+), 0)
 console.log(ticketPriceTotal);
 
 // ==== Challenge 5: Be Creative ====
 // Now that you have used .forEach(), .map(), .filter(), and .reduce().  I want you to think of potential problems you could solve given the data set and the 5k fun run theme.  Try to solve 3 unique problems using one or many of the array methods listed above.
 
 // Problem 1
 
+let emails = []
+
+runners.forEach(({email}) => {
+    emails.push(email)
+})
+
+console.log("Emails:", emails)
+
 // Problem 2
 
-// Problem 3
+let govEmails = emails.filter(email => email.includes(".gov"))
+
+console.log("Government Emails:", govEmails)
+
+// Problem 3
+
+let emailDomains = emails.map(email => {
+    let splitEmail = email.split("@")
+    return splitEmail[splitEmail.length - 1]
+})
+
+console.log("Email Domains:", emailDomains)

assignments/closure.js

@@ -1,19 +1,51 @@
 // ==== Challenge 1: Write your own closure ====
 // Write a simple closure of your own creation.  Keep it simple!
 
+const random = till => () => Math.floor(Math.random() * till + 1)
+
+const randomTill10 = random(10)
+const randomTill100 = random(100)
+const randomTill1000 = random(1000)
+
+console.log(randomTill10())
+console.log(randomTill100())
+console.log(randomTill1000())
 
 // ==== Challenge 2: Create a counter function ====
 const counter = () => {
-  // Return a function that when invoked increments and returns a counter variable.
+  let num = 1;
+  return () => num++
 };
-// Example usage: const newCounter = counter();
-// newCounter(); // 1
-// newCounter(); // 2
+
+const newCounter = counter();
+
+console.log(newCounter()); // 1
+console.log(newCounter()); // 2
 
 
 // ==== Challenge 3: Create a counter function with an object that can increment and decrement ====
 const counterFactory = () => {
   // Return an object that has two methods called `increment` and `decrement`.
   // `increment` should increment a counter variable in closure scope and return it.
   // `decrement` should decrement the counter variable and return it.
+  let counter = 0
+
+  return {
+    increment: function() {
+      return counter++
+    }, 
+    decrement: function () {
+      return counter--
+    }
+  }
 };
+
+const counter1 = counterFactory()
+const counter2 = counterFactory()
+
+console.log("Counter 1:", counter1.increment())
+console.log("Counter 1:", counter1.increment())
+
+console.log("Counter 2:", counter2.increment())
+console.log("Counter 2:", counter2.increment())
+

assignments/function-conversion.js

@@ -1,23 +1,17 @@
 // Take the commented ES5 syntax and convert it to ES6 arrow Syntax
 
-// let myFunction = function () {};
+ let myFunction = () => {};
 
-// let anotherFunction = function (param) {
-//   return param;
-// };
+ let anotherFunction = param => param
 
-// let add = function (param1, param2) {
-//   return param1 + param2;
-// };
-// add(1,2);
 
-let subtract = function (param1, param2) {
-  return param1 - param2;
-};
-subtract(1,2); //?
+ let add = (param1, param2) => param1 + param2
+ add(1,2);
+
+let subtract = (param1, param2) => param1 - param2
+subtract(1,2); 
 
 exampleArray = [1,2,3,4];
-// const triple = exampleArray.map(function (num) {
-//   return num * 3;
-// });
-// console.log(triple);
+
+const triple = exampleArray.map(num => num * 3)
+console.log(triple);