London10_Olha-Danylevska_JavaScript-Core1_Coursework_week3

1-exercises/A-undefined/exercise.js

@@ -13,12 +13,23 @@
 let a;
 console.log(a);
 
+//because "a" did not assign to any value
+// let a = 2;
+// console.log(a)
+
 
 // Example 2
 function sayHello() {
     let message = "Hello";
 }
 
+//I think because 'message' is declared but its value is never read.
+
+// function sayHello() {
+//     let message = "Hello";
+//     return message
+// }
+
 let hello = sayHello();
 console.log(hello);
 
@@ -28,9 +39,20 @@ function sayHelloToUser(user) {
     console.log(`Hello ${user}`);
 }
 
+
 sayHelloToUser();
 
+// any returned value
+// function sayHelloToUser(user) {
+//     let userName = user
+//     console.log(`Hello ${userName}`);
+//     return `Hello ${userName}`
+// }
+
+
 
 // Example 4
-let arr = [1,2,3];
+let arr = [1, 2, 3];
 console.log(arr[3]);
+
+//non-existing array element

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
@@ -19,3 +19,7 @@ console.log(mentors);
   [1,2,3,4,5,6,7,8,9,10]
   ['Daniel', 'Irina', 'Rares']
 */
+
+
+
+

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
 }
 
 /* 

1-exercises/C-array-get-set/exercises2.js

@@ -7,6 +7,7 @@
 */
 
 let numbers = [1, 2, 3]; // Don't change this array literal declaration
+numbers.push(4)
 
 /* 
   DO NOT EDIT BELOW THIS LINE

1-exercises/D-for-loop/exercise.js

@@ -28,6 +28,12 @@ const AGES = [
 
 // 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/E-while-loop-with-array/exercise.js

@@ -17,7 +17,14 @@ const BIRTHDAYS = [
 ];
 
 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"

2-mandatory/1-weather-report.js

@@ -13,13 +13,21 @@
 
 function getTemperatureReport(cities) {
     // TODO
+    const reports = [];
+
+
+    for (item of cities) {
+        reports.push(`The temperature in ${item} is ${temperatureService(item)} degrees`)
+    }
+
+    return reports
 }
 
 
 /* ======= TESTS - DO NOT MODIFY ===== */
 
 function temperatureService(city) {
-    let temparatureMap  = new Map();
+    let temparatureMap = new Map();
 
     temparatureMap.set('London', 10);
     temparatureMap.set('Paris', 12);
@@ -28,10 +36,15 @@ function temperatureService(city) {
     temparatureMap.set('Mumbai', 29);
     temparatureMap.set('São Paulo', 23);
     temparatureMap.set('Lagos', 33);
-    
+
     return temparatureMap.get(city);
 }
 
+test("test should return array the same length as an argument", () => {
+    let usersCities = ["London", "Paris", "São Paulo"];
+    expect(getTemperatureReport(usersCities).length).toEqual(3);
+});
+
 test("should return a temperature report for the user's cities", () => {
     let usersCities = [
         "London",

2-mandatory/2-financial-times.js

@@ -5,6 +5,13 @@
     Implement the function below, which will return a new array containing only article titles which will fit.
 */
 function potentialHeadlines(allArticleTitles) {
+    let articlesWhichFit = []
+    for (item of allArticleTitles) {
+        if (item.length < 65) {
+            articlesWhichFit.push(item)
+        }
+    }
+    return articlesWhichFit
     // TODO
 }
 
@@ -14,7 +21,15 @@ function potentialHeadlines(allArticleTitles) {
     (you can assume words will always be seperated by a space)
 */
 function titleWithFewestWords(allArticleTitles) {
-    // TODO
+    let smallest = allArticleTitles[0]
+    for (i = 0; i < allArticleTitles.length; i++) {
+        if (smallest.length > allArticleTitles[i].length) {
+            smallest = allArticleTitles[i]
+        }
+    }
+
+    return smallest
+
 }
 
 /*
@@ -23,19 +38,40 @@ 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 numberArray = []
+    for (item of allArticleTitles) {
+        for (element of item) {
+            element = parseInt(element)
+            if (item.includes(element)) {
+                numberArray.push(item)
+                break
+            }
+        }
+    }
+    return numberArray;
 }
 
 /*
     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
+    sumOfStrings = []
+    for (item of allArticleTitles) {
+        let itemLength = item.length
+        sumOfStrings.push(itemLength)
+    }
+    const initialValue = 0;
+    const sumWithInitial = sumOfStrings.reduce(
+        (accumulator, currentValue) => accumulator + currentValue,
+        initialValue
+    );
+    return Math.floor(Math.round(sumWithInitial / allArticleTitles.length))
 }
 
 
 
+
 /* ======= List of Articles - DO NOT MODIFY ===== */
 const ARTICLE_TITLES = [
     "Streaming wars drive media groups to spend more than $100bn on new content",

2-mandatory/3-stocks.js

@@ -8,7 +8,7 @@
 */
 
 /* ======= Stock data - DO NOT MODIFY ===== */
-const STOCKS = ["aapl", "msft", "amzn", "googl", "tsla"];
+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
@@ -34,9 +34,21 @@ const CLOSING_PRICES_LAST_5_DAYS_FOR_ALL_STOCKS = [
         Functions can help with this!
 */
 function getAveragePrices(closingPricesForAllStocks) {
-    // TODO
+    arrayOfPrices = []
+    for (item of closingPricesForAllStocks) {
+        const initialValue = 0;
+        const sumWithInitial = item.reduce(
+            (accumulator, currentValue) => accumulator + currentValue,
+            initialValue
+        );
+        let averagePrice = sumWithInitial / item.length
+        let averagePriceDecimal = Math.round(averagePrice * 100) / 100
+        arrayOfPrices.push(averagePriceDecimal)
+    }
+    return arrayOfPrices
 }
 
+
 /*
     We also want to see what the change in price is from the first day to the last day for each stock.
     Implement the below function, which
@@ -48,9 +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 eachArrayOfDifference = []
+    for (element of closingPricesForAllStocks) {
+        for (i = 0; i < element.length; i++) {
+            let lastPrice = element.slice(-1)
+            let difference = lastPrice - element[i]
+            let differenceWithDecimal = Math.round(difference * 100) / 100
+            eachArrayOfDifference.push(differenceWithDecimal)
+            break
+        }
+    }
+    return eachArrayOfDifference
 }
-
 /*
     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 +85,23 @@ function getPriceChanges(closingPricesForAllStocks) {
     The price should be shown with exactly 2 decimal places.
 */
 function highestPriceDescriptions(closingPricesForAllStocks, stocks) {
-    // TODO
+    let arrayOfAnswers = []
+    let arrayOfStrings = []
+    for (item of closingPricesForAllStocks) {
+        for (i = 0; i < item.length; i++)
+            if (item[0] < item[i]) {
+                item[0] = item[i]
+            }
+        let answer = item[0]
+        answer = answer.toFixed(2)
+        console.log("ANSWER", answer)
+        arrayOfAnswers.push(answer)
+    }
+    for (i = 0; i < arrayOfAnswers.length; i++) {
+        arrayOfStrings.push(`The highest price of ${stocks[i]} in the last 5 days was ${arrayOfAnswers[i]}`)
+    }
+
+    return arrayOfStrings
 }
 
 

3-extra/1-radio-stations.js

@@ -13,11 +13,26 @@
  * - Should return this array to use in other functions
  */
 
+
 // `getAllFrequencies` goes here
 
+function getAllFrequencies() {
+  let startFrequency = 87
+  let arrayOfFrequencies = []
+  while (startFrequency <= 108) {
+    arrayOfFrequencies.push(startFrequency)
+    startFrequency = startFrequency + 1
+  }
+  return arrayOfFrequencies
+}
+
+
+
 /**
  * Next, let's write a function that gives us only the frequencies that are radio stations.
  * Call this function `getStations`.
+ * 
+
  *
  * This function should:
  * - Get the available frequencies from `getAllFrequencies`
@@ -26,6 +41,17 @@
  */
 // `getStations` goes here
 
+
+function getStations(allFrequencies) {
+  let arrayOfRadioStations = []
+  allFrequencies = getAllFrequencies()
+  for (i = 0; i < allFrequencies.length; i++) {
+    if (isRadioStation(allFrequencies[i])) {
+      arrayOfRadioStations.push(allFrequencies[i])
+    }
+  }
+  return arrayOfRadioStations
+}
 /*
  * ======= TESTS - DO NOT MODIFY =======
  * Note: You are not expected to understand everything below this comment!
@@ -55,6 +81,9 @@ function isRadioStation(frequency) {
   return getAvailableStations().includes(frequency);
 }
 
+
+
+
 test("getAllFrequencies() returns all frequencies between 87 and 108", () => {
   expect(getAllFrequencies()).toEqual([
     87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104,