Solutions to tasks

01/app.js

@@ -0,0 +1,8 @@
+const users = ["Adam kowalski", "Jan Brzoza", "Sandra Malinowska", "Nikola Matlik", "Wiktoria Wiśniowska"];
+
+for(let i = 0; i < users.length; i++){
+    if(i % 2 === 0){
+        console.log(users[i])
+    }
+}
+console.log("tablica zawiera: " + users.length + " elementów");

02/app.js

@@ -20,4 +20,16 @@ function createRandomArray() {
 
 function getRandomInteger(min, max) {
     return Math.round(Math.random() * (max-min) + min);
-}
+}
+
+console.log("Wyświetlenie wszystkich elementów tablicy przy pomocy pętli for: ")
+
+for(let i = 0; i < randomArray.length; i++){
+    console.log(randomArray[i]);
+}
+
+console.log("Wyświetlenie wszystkich elementów tablicy przy pomocy metody foreach")
+
+randomArray.forEach(element => {
+    console.log(element)
+});

03/app.js

@@ -1,2 +1,10 @@
-const n = 24;
-const oddNumbers = [];
+const n = 100;
+const oddNumbers = [];
+
+for(let i = 0; i <= n; i++){
+    if( i > 0 && i % 2 ===1){
+        oddNumbers.push(i);
+    }
+}
+
+console.log(oddNumbers);

04/app.js

@@ -1 +1,11 @@
-const years = [1980, 1934, 2002, 2019];
+const years = [1980, 1934, 2002, 2019];
+
+const numbersOfYears = years.map(calcNumberOfYears);
+
+function calcNumberOfYears(element, index, array){
+    const currentYear = new Date().getFullYear();
+    return currentYear - element;
+}
+
+console.log(numbersOfYears)
+

05/app.js

@@ -1 +1,12 @@
-const numbers = [1, 2, 3, 4, 5, 6, 7];
+const numbers = [1, 2, 3, 4, 5, 6, 7];
+const evenNumbers = numbers.filter((number) => {
+    if(number % 2 === 0){
+        return number;
+    }
+})
+
+const sum  = evenNumbers.reduce(function(prevValue, currentValue){
+    return prevValue + currentValue;
+});
+
+console.log(sum)