WM4 - class 1 - Simeon Bikov - JS - week 3

.vscode/launch.json

@@ -0,0 +1,15 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "pwa-chrome",
+            "request": "launch",
+            "name": "Launch Chrome against localhost",
+            "url": "http://localhost:8080",
+            "webRoot": "${workspaceFolder}"
+        }
+    ]
+}

1-exercises/A-undefined/exercise.js

@@ -9,12 +9,12 @@
     For each example, can you explain why we are seeing undefined?
 */
 
-// Example 1
+// Example 1 - variable has not been assigned
 let a;
 console.log(a);
 
 
-// Example 2
+// Example 2 - value in the function was not returned
 function sayHello() {
     let message = "Hello";
 }
@@ -23,14 +23,14 @@ let hello = sayHello();
 console.log(hello);
 
 
-// Example 3
+// Example 3 - function has no parameter
 function sayHelloToUser(user) {
     console.log(`Hello ${user}`);
 }
 
 sayHelloToUser();
 
 
-// Example 4
+// Example 4 - array does not have index number 3
 let arr = [1,2,3];
 console.log(arr[3]);

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

@@ -6,7 +6,17 @@
 */
 
 function evenNumbers(n) {
-    // TODO
+  let i = 0;
+  let j = 0;
+  let res = "";
+  while (i < n) {
+    if (j % 2 === 0) {
+      res += j + ",";
+      i++;
+    }
+    j++;
+  }
+  console.log(res.slice(0, -1));
 }
 
 evenNumbers(3); // should output 0,2,4

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

@@ -16,8 +16,14 @@ const BIRTHDAYS = [
     "November 15th"
 ];
 
+
 function findFirstJulyBDay(birthdays) {
-    // TODO
+  let i = 0;
+  const month = "July";
+  while (!(birthdays[i].includes(month))) {
+    i++;
+  }
+return birthdays[i];
 }
 
 console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"

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

@@ -7,7 +7,17 @@
 */
 
 function evenNumbersSum(n) {
-    // TODO
+    let i = 0;
+    let j = 0;
+    let sum = 0;
+    do {
+        if (j % 2 === 0) {
+            sum += j;
+            i++;
+        }
+    j++;
+    } while (i < n);
+return sum;
 }
 
 console.log(evenNumbersSum(3)); // should output 6

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

@@ -6,9 +6,8 @@
 
 
 // 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

@@ -26,7 +26,9 @@ const AGES = [
     49
 ];
 
-// TODO - Write for loop code here
+for (i = 0; i < WRITERS.length; i++) {
+    console.log(`${WRITERS[i]} is ${AGES[i]} years old`);
+}
 
 /*
 The output should look something like this:

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

@@ -11,6 +11,13 @@ let tubeStations = [
     "Tottenham Court Road"
 ];
 
+for (const station of tubeStations) {
+  console.log(station);
+}
 
 // TODO Use a for-of loop to capitalise and output each letter in the string seperately.
 let str = "codeyourfuture";
+
+for (const char of str) {
+  console.log(char.toUpperCase());
+}

2-mandatory/1-weather-report.js

@@ -12,7 +12,11 @@
 */
 
 function getTemperatureReport(cities) {
-    // TODO
+  let res = [];
+  for (const city of cities) {
+    res.push(`The temperature in ${city} is ${temperatureService(city)} degrees`);
+  }
+  return res;
 }
 
 

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

@@ -10,7 +10,11 @@ function generateRandomNumber() {
 }
 
 function getRandomNumberGreaterThan50() {
-    // TODO - implement using a do-while loop
+  let i = 0;
+  do {
+    i = generateRandomNumber();
+  } while (i < 51);
+  return i;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */

2-mandatory/3-financial-times.js

@@ -5,16 +5,24 @@
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
-    // TODO
+  let shortArticles = allArticleTitles.filter(title => title.length < 66); 
+  return shortArticles;
 }
 
 /*
     The editor of the FT likes short headlines with only a few words!
     Implement the function below, which returns the title with the fewest words.
     (you can assume words will always be seperated by a space)
 */
+
 function titleWithFewestWords(allArticleTitles) {
-    // TODO
+  let lengthOfTitles = [];
+  for (const articleTitle of allArticleTitles) {
+    lengthOfTitles.push(articleTitle.split(" ").length - 1);
+  }
+    const min = Math.min(...lengthOfTitles);
+    const index = lengthOfTitles.indexOf(min);
+  return allArticleTitles[index];
 }
 
 /*
@@ -23,15 +31,23 @@ function titleWithFewestWords(allArticleTitles) {
     (Hint: remember that you can also loop through the characters of a string if you need to)
 */
 function headlinesWithNumbers(allArticleTitles) {
-    // TODO
+  let digits = /\d+/;
+  let articlesWithNumbers = allArticleTitles.filter(articles => articles.match(digits));
+  return articlesWithNumbers;
 }
 
+
 /*
     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.
 */
+let sumOfTitlesLength = 0;
 function averageNumberOfCharacters(allArticleTitles) {
-    // TODO
+  for (const articleTitle of allArticleTitles) {
+    sumOfTitlesLength += articleTitle.length;
+  }
+  let averageChar = sumOfTitlesLength / allArticleTitles.length;
+  return Math.round(averageChar);
 }
 
 

2-mandatory/4-stocks.js

@@ -34,7 +34,19 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
         Functions can help with this!
 */
 function getAveragePrices(closingPricesForAllStocks) {
-    // TODO
+  let allAveragePrices = [];
+
+  for (const closingPricesForStock of closingPricesForAllStocks) {
+    let sum = 0;
+    let average = 0;
+
+    for (const price of closingPricesForStock) {
+      sum += price;
+    }
+    average = sum / closingPricesForStock.length;
+    allAveragePrices.push(parseFloat(average.toFixed(2)));
+  }
+  return allAveragePrices;
 }
 
 /*
@@ -48,7 +60,18 @@ function getAveragePrices(closingPricesForAllStocks) {
     The price change value should be rounded to 2 decimal places, and should be a number (not a string)
 */
 function getPriceChanges(closingPricesForAllStocks) {
-    // TODO
+  let changeInPrice = [];
+  let firstPrice = 0;
+  let lastPrice = 0;
+  let difference = 0;
+
+  for (const closingPricesForStock of closingPricesForAllStocks) {
+    firstPrice = closingPricesForStock[0];
+    lastPrice = closingPricesForStock[closingPricesForAllStocks.length - 1];
+    difference = lastPrice - firstPrice;
+    changeInPrice.push(parseFloat(difference.toFixed(2)));
+  }
+  return changeInPrice;
 }
 
 /*
@@ -64,7 +87,15 @@ function getPriceChanges(closingPricesForAllStocks) {
     The price should be shown with exactly 2 decimal places.
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
-    // TODO
+  let highestPriceForAllStock = [];
+  let highestPrice = 0;
+
+  for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+    highestPrice = Math.max(...closingPricesForAllStocks[i]);
+    highestPrice = highestPrice.toFixed(2);
+    highestPriceForAllStock[i] = `The highest price of ${stocks[i].toUpperCase()} in the last ${closingPricesForAllStocks.length} days was ${highestPrice}`;
+  }
+  return highestPriceForAllStock;
 }
 
 

3-extra/1-factorial.js

@@ -9,7 +9,11 @@
 */
 
 function factorial(input) {
-    // TODO
+  let sum = 1;
+  for (let i = input; i >= 1; i--) {
+    sum *= i;
+  }
+  return sum;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */

3-extra/2-array-of-objects.js

@@ -11,7 +11,17 @@
 */
 
 function getHighestRatedInEachGenre(books) {
-    // TODO
+  let sortedBooks = books.sort((b1, b2) => b1.rating < b2.rating ? 1 : b1.rating > b2.rating ? -1 : 0);
+  let highestRatedBook = [];
+  let arrOfGenres = [];
+
+  for (const book of sortedBooks) {
+    if (!arrOfGenres.includes(book.genre)) {
+      arrOfGenres.push(book.genre);
+      highestRatedBook.push(book.title);
+    }
+  }
+  return highestRatedBook;
 }
 
 

3-extra/3-fibonacci.js

@@ -14,7 +14,14 @@
 */
 
 function generateFibonacciSequence(n) {
-    // TODO
+  sequence = [0, 1];
+  let newNum = 0;
+
+  for (let i = 2; i < n; i++) {
+    newNum = sequence[i - 2] + sequence[i - 1];
+    sequence.push(newNum);
+  }
+  return sequence;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */