Manchester NW5-Doris Siu-JavaScript1-Week3

1-exercises/A-undefined/exercise.js

@@ -13,6 +13,8 @@
 let a;
 console.log(a);
 
+// We are seeing "undefined" for a here because even though we declared an "a" variable before but no value has been assigned to "a". 
+
 
 // Example 2
 function sayHello() {
@@ -22,6 +24,8 @@ function sayHello() {
 let hello = sayHello();
 console.log(hello);
 
+// We are seeing "undefined" here because there is no return value from hello which is a function.
+
 
 // Example 3
 function sayHelloToUser(user) {
@@ -30,7 +34,11 @@ function sayHelloToUser(user) {
 
 sayHelloToUser();
 
+// We are seeing "undefined" here because no argument is being passed into the function sayHelloToUser(user). 
 
 // Example 4
 let arr = [1,2,3];
 console.log(arr[3]);
+
+// We are seeing "undefined" here because there is no arr[3] in the array, the last item in the array is arr[2].
+

1-exercises/B-while-loop/exercise.js

@@ -7,6 +7,16 @@
 
 function evenNumbers(n) {
     // TODO
+let counter = 0;
+let arr = [];
+let num = 0;
+while (n>counter) {
+   arr[counter] = num;
+   num = num+2;
+   counter++; 
+}
+
+console.log (arr);
 }
 
 evenNumbers(3); // should output 0,2,4

1-exercises/C-while-loop-with-array/exercise.js

@@ -18,6 +18,15 @@ const BIRTHDAYS = [
 
 function findFirstJulyBDay(birthdays) {
     // TODO
+    let counter = 0;
+    while (birthdays[counter].includes("July") === false) {
+        counter++;
+    }
+
+    return birthdays[counter];
+
+
+
 }
 
 console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"

1-exercises/D-do-while/exercise.js

@@ -8,8 +8,20 @@
 
 function evenNumbersSum(n) {
     // TODO
+    let sum = 0;
+    let num = 0;
+    let counter = 0;
+    do {
+        sum += num;
+        num += 2;
+        counter++;
+
+    } while (counter<n);
+
+    return sum;
 }
 
+
 console.log(evenNumbersSum(3)); // should output 6
 console.log(evenNumbersSum(0)); // should output 0
 console.log(evenNumbersSum(10)); // should output 90

1-exercises/E-for-loop/exercise1.js

@@ -6,9 +6,7 @@
 
 
 // Change the below code to use a for loop instead of a while loop.
-let i = 0;
-while(i < 26) {
+for ( let i = 0; i < 26; i++) {
     console.log(String.fromCharCode(97 + i));
-    i++;
 }
 // The output shouldn't change.

1-exercises/E-for-loop/exercise2.js

@@ -28,6 +28,10 @@ const AGES = [
 
 // TODO - Write for loop code here
 
+for (let counter = 0; counter < WRITERS.length; counter++) {
+    console.log (`${WRITERS[counter]} is ${AGES[counter]} years old`);
+}
+
 /*
 The output should look something like this:
 

1-exercises/F-for-of-loop/exercise.js

@@ -11,6 +11,15 @@ let tubeStations = [
     "Tottenham Court Road"
 ];
 
+for (let item of tubeStations) {
+    console.log(item);
+}
+
 
 // TODO Use a for-of loop to capitalise and output each letter in the string seperately.
 let str = "codeyourfuture";
+
+for (let item of str) {
+    let converted = item.toUpperCase();
+    console.log(converted);
+}

2-mandatory/1-weather-report.js

@@ -11,10 +11,20 @@
         - Hint: you can call the temperatureService function from your function
 */
 
+cities1 = ['London', 'Paris','Barcelona','Dubai','Mumbai', 'São Paulo','Lagos'];
+
 function getTemperatureReport(cities) {
     // TODO
+    let arr = [];
+    for (let item of cities) {
+        let temp = temperatureService(item);
+        arr.push (`The temperature in ${item} is ${temp} degrees`); 
+    }
+    return arr;
 }
 
+getTemperatureReport(cities1);
+
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 

2-mandatory/2-retrying-random-numbers.js

@@ -5,20 +5,26 @@
 
 // This function shouldn't be changed
 function generateRandomNumber() {
-    console.log("Generating number...");
-    return Math.round(Math.random() * 100);
+  console.log("Generating number...");
+  return Math.round(Math.random() * 100);
 }
 
 function getRandomNumberGreaterThan50() {
-    // TODO - implement using a do-while loop
+  // TODO - implement using a do-while loop
+  let result = 0;
+  do {
+    result = generateRandomNumber();
+  } while (result <= 50);
+
+  return result;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 
 test("Returned value should always be greater than 50", () => {
-    expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
-    expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
-    expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
-    expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
-    expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
+  expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
+  expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
+  expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
+  expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
+  expect(getRandomNumberGreaterThan50()).toBeGreaterThan(50);
 });

2-mandatory/3-financial-times.js

@@ -5,7 +5,17 @@
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
-    // TODO
+  let fitTitleArr = [];
+  if (allArticleTitles == null) {
+    return fitTitleArr;
+  }
+  for (let title of allArticleTitles) {
+    if (title.length <= 65) {
+      fitTitleArr.push(title);
+    }
+  }
+  return fitTitleArr;
+  // TODO
 }
 
 /*
@@ -14,7 +24,15 @@ function potentialHeadlines(allArticleTitles) {
     (you can assume words will always be seperated by a space)
 */
 function titleWithFewestWords(allArticleTitles) {
-    // TODO
+  let countArr = [];
+  for (let title of allArticleTitles) {
+    let titleArr = title.split(" ");
+    countArr.push(titleArr);
+  }
+  let result = countArr.sort((a, b) => a.length - b.length)[0];
+  return result.join(" ");
+
+  // TODO
 }
 
 /*
@@ -23,59 +41,79 @@ function titleWithFewestWords(allArticleTitles) {
     (Hint: remember that you can also loop through the characters of a string if you need to)
 */
 function headlinesWithNumbers(allArticleTitles) {
-    // TODO
+  // TODO
+  let numTitleArr = [];
+  let conditions = ["1", "2", "3", "4", "5", "6", "7", "8", "9", "0"];
+  for (let title of allArticleTitles) {
+    if (conditions.some((el) => title.includes(el))) {
+      numTitleArr.push(title);
+    }
+  }
+  return numTitleArr;
 }
 
 /*
     The Financial Times wants to understand what the average number of characters in an article title is.
     Implement the function below to return this number - rounded to the nearest integer.
 */
 function averageNumberOfCharacters(allArticleTitles) {
-    // TODO
+  // TODO
+  let sum = 0;
+  let totalOfArticle = allArticleTitles.length;
+  for (let item of allArticleTitles) {
+    let strLength = item.length;
+    sum += strLength;
+  }
+  let average = sum / totalOfArticle;
+  return Math.round(average);
 }
 
-
-
 /* ======= List of Articles - DO NOT MODIFY ===== */
 const ARTICLE_TITLES = [
-    "Streaming wars drive media groups to spend more than $100bn on new content",
-    "Amazon Prime Video India country head: streaming is driving a TV revolution",
-    "Aerospace chiefs prepare for bumpy ride in recovery of long-haul flights",
-    "British companies look to muscle in on US retail investing boom",
-    "Libor to take firm step towards oblivion on New Year's Day",
-    "Audit profession unattractive to new recruits, says PwC boss",
-    "Chinese social media users blast Elon Musk over near miss in space",
-    "Companies raise over $12tn in 'blockbuster' year for global capital markets",
-    "The three questions that dominate investment",
-    "Brussels urges Chile's incoming president to endorse EU trade deal",
+  "Streaming wars drive media groups to spend more than $100bn on new content",
+  "Amazon Prime Video India country head: streaming is driving a TV revolution",
+  "Aerospace chiefs prepare for bumpy ride in recovery of long-haul flights",
+  "British companies look to muscle in on US retail investing boom",
+  "Libor to take firm step towards oblivion on New Year's Day",
+  "Audit profession unattractive to new recruits, says PwC boss",
+  "Chinese social media users blast Elon Musk over near miss in space",
+  "Companies raise over $12tn in 'blockbuster' year for global capital markets",
+  "The three questions that dominate investment",
+  "Brussels urges Chile's incoming president to endorse EU trade deal",
 ];
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 
 test("should only return potential headlines", () => {
-    expect(new Set(potentialHeadlines(ARTICLE_TITLES))).toEqual(new Set([
-        "British companies look to muscle in on US retail investing boom",
-        "Libor to take firm step towards oblivion on New Year's Day",
-        "Audit profession unattractive to new recruits, says PwC boss",
-        "The three questions that dominate investment"
-    ]));
+  expect(new Set(potentialHeadlines(ARTICLE_TITLES))).toEqual(
+    new Set([
+      "British companies look to muscle in on US retail investing boom",
+      "Libor to take firm step towards oblivion on New Year's Day",
+      "Audit profession unattractive to new recruits, says PwC boss",
+      "The three questions that dominate investment",
+    ])
+  );
 });
 
 test("should return an empty array for empty input", () => {
-    expect(potentialHeadlines([])).toEqual([]);
+  expect(potentialHeadlines([])).toEqual([]);
 });
 
 test("should return the title with the fewest words", () => {
-    expect(titleWithFewestWords(ARTICLE_TITLES)).toEqual("The three questions that dominate investment");
+  expect(titleWithFewestWords(ARTICLE_TITLES)).toEqual(
+    "The three questions that dominate investment"
+  );
 });
 
 test("should only return headlines containing numbers", () => {
-    expect(new Set(headlinesWithNumbers(ARTICLE_TITLES))).toEqual(new Set([
-        "Streaming wars drive media groups to spend more than $100bn on new content",
-        "Companies raise over $12tn in 'blockbuster' year for global capital markets"
-    ]));
+  expect(new Set(headlinesWithNumbers(ARTICLE_TITLES))).toEqual(
+    new Set([
+      "Streaming wars drive media groups to spend more than $100bn on new content",
+      "Companies raise over $12tn in 'blockbuster' year for global capital markets",
+    ])
+  );
 });
 
 test("should return the average number of characters in a headline", () => {
-    expect(averageNumberOfCharacters(ARTICLE_TITLES)).toEqual(65);
+  expect(averageNumberOfCharacters(ARTICLE_TITLES)).toEqual(65);
 });