first day solutions

solutions/day-01/level1.js

@@ -0,0 +1,62 @@
+// Declare an empty array;
+const arr = [];
+
+// Declare an array with more than 5 number of elements
+const arrFivePlus = [0, 1, 2, 3, 4, 5, 6];
+
+// Find the length of your array
+console.log(arrFivePlus.length);
+
+// Get the first item, the middle item and the last item of the array
+console.log(arrFivePlus.indexOf(0));
+console.log(arrFivePlus.slice(3, 4));
+console.log(arrFivePlus.lastIndexOf(6));
+
+// Declare an array called mixedDataTypes, put different data types in the array and find the length of the array. The array size should be greater than 5
+const mixedDataTypes = [10, 'Happy', 'Code', true, !false, 'JS'];
+console.log(mixedDataTypes.length);
+
+// Declare an array variable name itCompanies and assign initial values Facebook, Google, Microsoft, Apple, IBM, Oracle and Amazon
+const itCompanies = ['Facebook', 'Google', 'Microsoft', 'Apple', 'IBM', 'Oracle', 'Amazon'];
+// Print the array using console.log()
+console.log(itCompanies);
+// Print the number of companies in the array
+console.log(itCompanies.length);
+// Print the first company, middle and last company
+const joinComp = itCompanies[0] + ', ' + itCompanies.slice(3, 4) + ', ' + itCompanies.slice(6, 7);
+console.log(joinComp);
+// Print out each company
+itCompanies.forEach((element) => {
+    console.log(element);
+});
+// Change each company name to uppercase one by one and print them out
+itCompanies.forEach((e) => {
+    let upCase = e.toUpperCase();
+    console.log(upCase);
+});
+// Print the array like as a sentence: Facebook, Google, Microsoft, Apple, IBM,Oracle and Amazon are big IT companies.
+let sent = ' and ' + itCompanies[6] + ' are big IT companies.';
+itCompanies.pop();
+console.log(itCompanies + sent);
+// Check if a certain company exists in the itCompanies array. If it exist return the company else return a company is not found
+if (itCompanies.includes('Apple') === true) {
+    console.log('Apple');
+} else {
+    console.log('Company is not found');
+}
+// Filter out companies which have more than one 'o' without the filter method
+itCompanies.forEach((element) => {
+    if (element.includes('o')) {
+        console.log(element);
+    }
+});
+
+// Sort the array using sort() method
+console.log(itCompanies.sort());
+// Reverse the array using reverse() method
+console.log(itCompanies.reverse());
+// Slice out the first 3 companies from the array
+console.log(itCompanies.slice(0, 3));
+// Slice out the last 3 companies from the array
+console.log(itCompanies.slice(3));
+// Slice out the middle IT company or companies from the array