CodeYourFuture · m4ndycheung · Mar 4, 2023 · Mar 4, 2023 · Mar 4, 2023 · Mar 4, 2023
diff --git a/1-exercises/A-undefined/exercise.js b/1-exercises/A-undefined/exercise.js
@@ -13,6 +13,8 @@
 let a;
 console.log(a);
 
+// the variable a hasn't been initialised i.e. it's not been assigned an initial value
+
 
 // Example 2
 function sayHello() {
@@ -22,6 +24,7 @@ function sayHello() {
 let hello = sayHello();
 console.log(hello);
 
+// the function won't return anything, so the variable hello will return undefined.
 
 // Example 3
 function sayHelloToUser(user) {
@@ -30,7 +33,12 @@ function sayHelloToUser(user) {
 
 sayHelloToUser();
 
+// the function needs an argument called user to be passed through it.
+// in line 34, there are no arguments being passed through the function so it will return Hello undefined.
 
 // Example 4
 let arr = [1,2,3];
 console.log(arr[3]);
+
+// so the array begins at index 0 and ends at index 2.
+// there is no value assigned at index 3 so it'll return undefined.
diff --git a/1-exercises/B-array-literals/exercise.js b/1-exercises/B-array-literals/exercise.js
@@ -4,8 +4,8 @@
   Declare some variables assigned to arrays of values
 */
 
-let numbers = []; // add numbers from 1 to 10 into this array
-let mentors; // Create an array with the names of the mentors: Daniel, Irina and Rares
+let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; // add numbers from 1 to 10 into this array
+let mentors = ["Daniel", "Irina", "Rares"]; // Create an array with the names of the mentors: Daniel, Irina and Rares
 
 /* 
   DO NOT EDIT BELOW THIS LINE

diff --git a/1-exercises/C-array-get-set/exercise.js b/1-exercises/C-array-get-set/exercise.js
@@ -5,11 +5,11 @@
 */
 
 function first(arr) {
-  return; // complete this statement
+  return arr[0]; // complete this statement
 }
 
 function last(arr) {
-  return; // complete this statement
+  return arr[arr.length - 1]; // complete this statement
 }
 
 /* 

diff --git a/1-exercises/C-array-get-set/exercises2.js b/1-exercises/C-array-get-set/exercises2.js
@@ -7,6 +7,8 @@
 */
 
 let numbers = [1, 2, 3]; // Don't change this array literal declaration
+numbers.push(4);
+numbers[0] = 1;
 
 /* 
   DO NOT EDIT BELOW THIS LINE

diff --git a/1-exercises/D-for-loop/exercise.js b/1-exercises/D-for-loop/exercise.js
@@ -28,6 +28,13 @@ const AGES = [
 
 // TODO - Write for loop code here
 
+for (i = 0; i < WRITERS.length; i++) {
+    let writersName = WRITERS[i];
+    let writersAge = AGES[i];
+
+    console.log(`${writersName} is ${writersAge} years old!`);
+}
+
 /*
 The output should look something like this:
 

diff --git a/1-exercises/E-while-loop-with-array/exercise.js b/1-exercises/E-while-loop-with-array/exercise.js
@@ -11,13 +11,21 @@ const BIRTHDAYS = [
     "April 5th",
     "May 3rd",
     "July 11th",
-    "July 17th",
+    "July 17th",-
     "September 28th",
     "November 15th"
 ];
 
 function findFirstJulyBDay(birthdays) {
-    // TODO
+    let i = 0;
+
+    while (i < birthdays.length) {
+        if (birthdays[i].includes("July")) {
+            return birthdays[i];
+        }
+
+        i++;
+    }
 }
 
 console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"
diff --git a/2-mandatory/1-weather-report.js b/2-mandatory/1-weather-report.js
@@ -12,9 +12,18 @@
 */
 
 function getTemperatureReport(cities) {
-    // TODO
-}
+    let temperatureReportResults = [ ];
+
+    for (i = 0; i < cities.length; i++) {
+        let city = cities[i];
+        let temperature = temperatureService(city);
+        let reportPhrasing = `The temperature in ${city} is ${temperature} degrees`;
 
+        temperatureReportResults.push(reportPhrasing);
+    }
+
+    return temperatureReportResults;
+}
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 

diff --git a/2-mandatory/2-financial-times.js b/2-mandatory/2-financial-times.js
@@ -1,11 +1,19 @@
 /*
-    Imagine you are working on the Financial Times web site! They have a list of article titles stored in an array.
+    Imagine you are working on the Financial Times website! They have a list of article titles stored in an array.
 
     The home page of the web site has a headline section, which only has space for article titles which are 65 characters or less.
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
-    // TODO
+    let titlesShortEnough = [ ];
+
+    for (const title of allArticleTitles) {
+        if(title.length <= 65) {
+            titlesShortEnough.push(title);
+        } 
+    }
+
+    return titlesShortEnough;
 }
 
 /*
@@ -14,24 +22,59 @@ function potentialHeadlines(allArticleTitles) {
     (you can assume words will always be seperated by a space)
 */
 function titleWithFewestWords(allArticleTitles) {
-    // TODO
-}
 
+    let smallestTitle = allArticleTitles[0];
+
+    for (i = 1; i < allArticleTitles.length; i++) {
+
+        if (smallestTitle.split(" ").length > allArticleTitles[i].split(" ").length) {
+            smallestTitle = allArticleTitles[i];
+        }
+    }
+   return smallestTitle;
+}
 /*
     The editor of the FT has realised that headlines which have numbers in them get more clicks!
     Implement the function below to return a new array containing all the headlines which contain a number.
     (Hint: remember that you can also loop through the characters of a string if you need to)
 */
+
 function headlinesWithNumbers(allArticleTitles) {
-    // TODO
+    let headlinesWithNumbers = [ ];
+    const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
+
+    for (i = 0; i < allArticleTitles.length; i++) {
+        if(numbers.some(element => allArticleTitles[i].includes(element))) {
+            headlinesWithNumbers.push(allArticleTitles[i]);
+        }
+    }
+    return headlinesWithNumbers;
 }
 
 /*
     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
+    // To store the total characters per title
+    let totalCharactersPerTitle = [ ];
+
+    // To count the characters per title and add them to totalCharactersPerTitle
+    for (i = 0; i < allArticleTitles.length; i++) {  
+        let countCharacters = allArticleTitles[i].length;
+        totalCharactersPerTitle.push(countCharacters);
+    }
+
+    // To store the sum of total characters
+    let totalCharacters = 0;
+    totalCharactersPerTitle.forEach( item => {
+        totalCharacters += item;
+    }) 
+
+    // To work out the average and round to the nearest integer
+    let averageNumberOfCharacters = Math.round(totalCharacters / (allArticleTitles.length));
+
+    return averageNumberOfCharacters;
 }
 
 

diff --git a/2-mandatory/3-stocks.js b/2-mandatory/3-stocks.js
@@ -1,7 +1,7 @@
 /*
     THESE EXERCISES ARE QUITE HARD. JUST DO YOUR BEST, AND COME WITH QUESTIONS IF YOU GET STUCK :)
 
-    Imagine we a working for a finance company. Below we have:
+    Imagine we are working for a finance company. Below we have:
         - an array of stock tickers
         - an array of arrays containing the closing price for each stock in each of the last 5 days.
             For example, CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS[2] contains the prices for the last 5 days for STOCKS[2] (which is amzn)
@@ -34,7 +34,21 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
         Functions can help with this!
 */
 function getAveragePrices(closingPricesForAllStocks) {
-    // TODO
+    // for storing averages of each company's stock over 5 days
+    let averagePriceOverFiveDays = [ ];
+
+    // This loop cycles through each stock, the i is the 5 day stock for AAPL, MSFT etc.
+    for (i = 0; i < closingPricesForAllStocks.length; i++) {
+        let totalStock = 0;
+        closingPricesForAllStocks[i].forEach((element) => {
+            totalStock += element;
+        });
+        let calculateAverage = totalStock / closingPricesForAllStocks[i].length;
+        let roundAverage = Math.round(calculateAverage * 100) / 100;
+        averagePriceOverFiveDays.push(roundAverage);
+    }
+
+    return averagePriceOverFiveDays;
 }
 
 /*
@@ -47,10 +61,28 @@ function getAveragePrices(closingPricesForAllStocks) {
                 (Apple's price on the 5th day) - (Apple's price on the 1st day) = 172.99 - 179.19 = -6.2
     The price change value should be rounded to 2 decimal places, and should be a number (not a string)
 */
-function getPriceChanges(closingPricesForAllStocks) {
-    // TODO
+
+
+function getPriceChanges(array) {
+
+    let changeInPrice = [ ];
+
+    for (i = 0; i < array.length; i++) {
+        let closingPricesArray = array;
+        let lengthOfInnerArray = closingPricesArray[i].length;
+        let fifthDayPrice = closingPricesArray[i][lengthOfInnerArray - 1];
+        let firstDayPrice = closingPricesArray[i][0];
+
+        let fifthDayMinusFirstDayRounded = Math.round((fifthDayPrice - firstDayPrice) * 100) / 100;
+
+        changeInPrice.push(fifthDayMinusFirstDayRounded);
+    }
+
+    return changeInPrice;
 }
 
+
+
 /*
     As part of a financial report, we want to see what the highest price was for each stock in the last 5 days.
     Implement the below function, which
@@ -64,7 +96,28 @@ function getPriceChanges(closingPricesForAllStocks) {
     The price should be shown with exactly 2 decimal places.
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
-    // TODO
+    let maxPrices = [ ];
+    let stockNames = stocks;
+    let maxStockDescriptions = [ ];
+
+    for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+        let currentMax = closingPricesForAllStocks[i][0];
+
+        for (let j = 0; j < closingPricesForAllStocks[i].length; j++) {
+            let currentElement = closingPricesForAllStocks[i][j];
+
+            if (currentElement >= currentMax) {
+                currentMax = currentElement;
+            }
+        }
+
+        let capitaliseStockNames = stockNames[i].toUpperCase();
+
+        maxPrices.push(currentMax.toFixed(2));
+        maxStockDescriptions.push(`The highest price of ${capitaliseStockNames} in the last 5 days was ${maxPrices[i]}`)
+    }
+
+    return maxStockDescriptions;
 }