CodeYourFuture · Dawit-Dev · Aug 16, 2022 · Aug 20, 2022 · simeonbikov · Aug 26, 2022
diff --git a/1-exercises/A-undefined/exercise.js b/1-exercises/A-undefined/exercise.js
@@ -13,14 +13,18 @@
 let a;
 console.log(a);
 
+//A variable was declared but no value was assigned to it.
 
 // Example 2
 function sayHello() {
     let message = "Hello";
 }
+//when a function does not return anything
 
 let hello = sayHello();
 console.log(hello);
+
+// executing a function that produces no output
 
 
 // Example 3
@@ -30,7 +34,10 @@ function sayHelloToUser(user) {
 
 sayHelloToUser();
 
+// A function that is declared with a parameter but receives no arguments
 
 // Example 4
 let arr = [1,2,3];
 console.log(arr[3]);
+
+// The index does not exist in the array.
diff --git a/1-exercises/B-while-loop/exercise.js b/1-exercises/B-while-loop/exercise.js
@@ -6,9 +6,24 @@
 */
 
 function evenNumbers(n) {
-    // TODO
-}
+
+ let arr = [];
+   let i = 0;
+   while (n > arr.length) {
+     if (i % 2 === 0) {
+       arr.push(i);
+     }
+     i++;
+   }
+
+   console.log(arr.toString());
+ }
+
+
 
 evenNumbers(3); // should output 0,2,4
 evenNumbers(0); // should output nothing
 evenNumbers(10); // should output 0,2,4,6,8,10,12,14,16,18
+
+
+
diff --git a/1-exercises/C-while-loop-with-array/exercise.js b/1-exercises/C-while-loop-with-array/exercise.js
@@ -17,7 +17,14 @@ const BIRTHDAYS = [
 ];
 
 function findFirstJulyBDay(birthdays) {
-    // TODO
+   let i = 0;
+  while (i < birthdays.length) {
+    let month = birthdays[i].substr(0, 3);
+    if (month === "Jul") {
+      return birthdays[i];
+    }
+    i++;
+  }
 }
 
 console.log(findFirstJulyBDay(BIRTHDAYS)); // should output "July 11th"
diff --git a/1-exercises/D-do-while/exercise.js b/1-exercises/D-do-while/exercise.js
@@ -7,7 +7,18 @@
 */
 
 function evenNumbersSum(n) {
-    // TODO
+let i = 0;
+  const evenNum = [];
+  do {
+    if (i % 2 === 0) {
+       evenNum.push(i);
+    }
+    i++
+  } while (n > evenNum.length)
+
+  let sum = evenNum.reduce((acc, curr) => acc + curr, 0);
+  return sum;
+
 }
 
 console.log(evenNumbersSum(3)); // should output 6

diff --git a/1-exercises/E-for-loop/exercise1.js b/1-exercises/E-for-loop/exercise1.js
@@ -6,9 +6,13 @@
 
 
 // Change the below code to use a for loop instead of a while loop.
-let i = 0;
-while(i < 26) {
+// let i = 0;
+// while(i < 26) {
+//     console.log(String.fromCharCode(97 + i));
+//     i++;
+// }
+
+for (let i = 0; i < 26; i++) {
     console.log(String.fromCharCode(97 + i));
-    i++;
 }
 // The output shouldn't change.
diff --git a/1-exercises/E-for-loop/exercise2.js b/1-exercises/E-for-loop/exercise2.js
@@ -27,7 +27,10 @@ const AGES = [
 ];
 
 // TODO - Write for loop code here
-
+for (let i = 0; i < WRITERS.length; i++) {
+    console.log(`${WRITERS[i]} is ${AGES[i]} years old`)
+}
+
 /*
 The output should look something like this:
 

diff --git a/1-exercises/F-for-of-loop/exercise.js b/1-exercises/F-for-of-loop/exercise.js
@@ -10,7 +10,12 @@ let tubeStations = [
     "Oxford Street",
     "Tottenham Court Road"
 ];
-
+for (let arr of tubeStations) {
+    console.log(arr);
+}
 
 // TODO Use a for-of loop to capitalise and output each letter in the string seperately.
 let str = "codeyourfuture";
+ for (arr of str){
+    console.log(arr.toUpperCase())
+}
diff --git a/2-mandatory/1-weather-report.js b/2-mandatory/1-weather-report.js
@@ -12,9 +12,15 @@
 */
 
 function getTemperatureReport(cities) {
-    // TODO
+    const temp = [];
+    for (let i = 0; i < cities.length; i++) {
+        temp.push('The temperature in ' + cities[i] + ' is ' + temperatureService(cities[i]) + ' degrees');
+    }
+    return temp;
 }
 
+// temp.push(`The temperature in ${cities[i]} is ${temperatureService(cities[i])} degrees`)
+
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 

diff --git a/2-mandatory/2-retrying-random-numbers.js b/2-mandatory/2-retrying-random-numbers.js
@@ -10,7 +10,11 @@ function generateRandomNumber() {
 }
 
 function getRandomNumberGreaterThan50() {
-    // TODO - implement using a do-while loop
+    let i;
+    do {
+     i = generateRandomNumber();
+    } while (i <= 50)
+    return i;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== */

diff --git a/2-mandatory/3-financial-times.js b/2-mandatory/3-financial-times.js
@@ -4,34 +4,76 @@
     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
+    return allArticleTitles.filter(title => title.length <= 65)
+
+    //  let newArray = [];
+    // for (let i = 0; i < allArticleTitles.length; i++){
+    //     if (allArticleTitles[i].length <= 65) {
+    //         newArray.push(allArticleTitles[i])
+    //     }
+    // }
+    // return newArray;
 }
+
 
 /*
     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 array = allArticleTitles[0].split(" ").length;
+    let spaceCount;
+    for (let i = 0; i < allArticleTitles.length; i++) {
+        wordCount = allArticleTitles[i].split(" ").length;
+        if (wordCount < array) {
+            array = wordCount;
+            spaceCount = i;
+        }
+    }
+    return allArticleTitles[spaceCount];
 }
 
+
 /*
     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
+    return allArticleTitles.filter(headline => /[0-9]/.test(headline));
+
+    //  let result = [];
+    // for (let i = 0; i < allHeadLineTitles.length; i++) {
+    //     let innersentece = allArticleTitles[i]
+    //     for (let j = 0; j < innersentece.length; j++){
+    //         let value = innersentece[j]
+    //         if (!isNaN(value) && value != " ") 
+    //         {
+    //              result.push(innersentece)
+    //              break;
+    //          }            
+    //     }
+    // }
+    // return result;
 }
 
 /*
     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
+    let charCountSum = 0;
+    for (let i = 0; i < allArticleTitles.length; i++){
+        charCountSum += allArticleTitles[i].length;
+    }
+    let average = charCountSum / allArticleTitles.length;
+    return Math.round(average);    
 }
 
 

diff --git a/2-mandatory/4-stocks.js b/2-mandatory/4-stocks.js
@@ -11,11 +11,11 @@
 const STOCKS = ["aapl", "msft", "amzn", "googl", "tsla"];
 
 const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
-    [179.19, 180.33, 176.28, 175.64, 172.99], // AAPL
-    [340.69, 342.45, 334.69, 333.20, 327.29], // MSFT
-    [3384.44, 3393.39, 3421.37, 3420.74, 3408.34], // AMZN
-    [2951.88, 2958.13, 2938.33, 2928.30, 2869.45], // GOOGL
-    [1101.30, 1093.94, 1067.00, 1008.87, 938.53] // TSLA
+  [179.19, 180.33, 176.28, 175.64, 172.99], // AAPL
+  [340.69, 342.45, 334.69, 333.2, 327.29], // MSFT
+  [3384.44, 3393.39, 3421.37, 3420.74, 3408.34], // AMZN
+  [2951.88, 2958.13, 2938.33, 2928.3, 2869.45], // GOOGL
+  [1101.3, 1093.94, 1067.0, 1008.87, 938.53], // TSLA
 ];
 
 /*
@@ -34,7 +34,17 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
         Functions can help with this!
 */
 function getAveragePrices(closingPricesForAllStocks) {
-    // TODO
+  let arr = [];
+  let average = 0;
+  for (const stockPrices of closingPricesForAllStocks) {
+    let stockSum = 0;
+    for (const price of stockPrices) {
+      stockSum += price;
+    }
+    average = parseFloat((stockSum / stockPrices.length).toFixed(2));
+    arr.push(average);
+  }
+  return arr;
 }
 
 /*
@@ -48,7 +58,14 @@ 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 changeArray = [];
+  for (const stockPrices of closingPricesForAllStocks) {
+    let priceChange = parseFloat(
+      (stockPrices[stockPrices.length - 1] - stockPrices[0]).toFixed(2)
+    );
+    changeArray.push(priceChange);
+  }
+  return changeArray;
 }
 
 /*
@@ -64,31 +81,52 @@ function getPriceChanges(closingPricesForAllStocks) {
     The price should be shown with exactly 2 decimal places.
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
-    // TODO
+  const sortedPrices = closingPricesForAllStocks.map((prices) =>
+    prices.sort((a, b) => b - a)
+  );
+  return sortedPrices.map((price, index) => {
+    return `The highest price of ${stocks[
+      index
+    ].toUpperCase()} in the last 5 days was ${price[0].toFixed(2)}`;
+  });
+  // let result = []
+  // for (let i = 0; i < closingPricesForAllStocks.length; i++) {
+  //     let companyStock = closingPricesForAllStocks[i];
+  //     let highestValue = companyStock[0];
+  //     for (let j = 0; j < companyStock.length; j++) {
+  //     if (companyStock[j] > highestValue) {
+  //             highestValue = companyStock[j]
+  //         }
+  //     }
+  //     result[i] = "The highest price of " + stocks[i].toUpperCase() + " in the last 5 days was " + highestValue.toFixed(2)
+  // }
+  // return result;
 }
-
+// console.log(
+//   highestPriceDescriptions(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS, STOCKS)
+// );
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 test("should return the average price for each stock", () => {
-    expect(getAveragePrices(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS)).toEqual(
-        [176.89, 335.66, 3405.66, 2929.22, 1041.93]
-    );
+  expect(getAveragePrices(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS)).toEqual([
+    176.89, 335.66, 3405.66, 2929.22, 1041.93,
+  ]);
 });
 
 test("should return the price change for each stock", () => {
-    expect(getPriceChanges(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS)).toEqual(
-        [-6.2, -13.4, 23.9, -82.43, -162.77]
-    );
+  expect(getPriceChanges(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS)).toEqual([
+    -6.2, -13.4, 23.9, -82.43, -162.77,
+  ]);
 });
 
 test("should return a description of the highest price for each stock", () => {
-    expect(highestPriceDescriptions(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS, STOCKS)).toEqual(
-        [
-            "The highest price of AAPL in the last 5 days was 180.33",
-            "The highest price of MSFT in the last 5 days was 342.45",
-            "The highest price of AMZN in the last 5 days was 3421.37",
-            "The highest price of GOOGL in the last 5 days was 2958.13",
-            "The highest price of TSLA in the last 5 days was 1101.30"
-        ]
-    );
+  expect(
+    highestPriceDescriptions(CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS, STOCKS)
+  ).toEqual([
+    "The highest price of AAPL in the last 5 days was 180.33",
+    "The highest price of MSFT in the last 5 days was 342.45",
+    "The highest price of AMZN in the last 5 days was 3421.37",
+    "The highest price of GOOGL in the last 5 days was 2958.13",
+    "The highest price of TSLA in the last 5 days was 1101.30",
+  ]);
 });
diff --git a/3-extra/1-factorial.js b/3-extra/1-factorial.js
@@ -9,9 +9,22 @@
 */
 
 function factorial(input) {
-    // TODO
+  let product = 1;
+  for (let i = input; i > 0; i--){
+    product = product * i;
+  }
+  return product;
+
+  // Alternate Solution
+  //  var f = [];
+  // if (input == 0 || input == 1)
+  //   return 1;
+  // if (f[input] > 0)
+  //   return f[input];
+  // return f[input] = factorial(input-1) * input;
 }
 
+
 /* ======= TESTS - DO NOT MODIFY ===== */
 
 test("3! should be 6", () => {