Pull request

Exercises/1-let.js

@@ -2,6 +2,6 @@
 
 // Define variable to store your name as a string
 
-let name = undefined;
+let name = 'Roman';
 
 module.exports = { name };

Exercises/2-const.js

@@ -2,6 +2,6 @@
 
 // Define constant to store your birth year as a number
 
-const year = undefined;
+const year = 2006;
 
 module.exports = { year };

Exercises/3-hello.js

@@ -2,6 +2,8 @@
 
 // Prepare function to print greeting with single argument
 
-const hello = null;
+const hello = (name) => {
+  console.log(`Hello, ${name}`);
+};
 
 module.exports = { hello };

Exercises/4-range.js

@@ -3,6 +3,14 @@
 // Implement function `range(start: number, end: number): array` returning
 // array with all numbers from the range [15, 30] including endpoints
 
-const range = null;
+const range = (start, number) => {
+  const arr = [];
+
+  for (let i = start; i <= number; i++) {
+    arr.push(i);
+  }
+
+  return arr;
+};
 
 module.exports = { range };

Exercises/5-range-odd.js

@@ -3,6 +3,16 @@
 // Implement function `rangeOdd(start: number, end: number)` returning
 // array with all odd numbers from the range [15, 30] including endpoints
 
-const rangeOdd = null;
+const isOdd = (a) => a % 2;
+
+const rangeOdd = (start, end) => {
+  const arr = [];
+
+  for (let i = start; i <= end; i++) {
+    if (isOdd(i)) arr.push(i);
+  }
+
+  return arr;
+};
 
 module.exports = { rangeOdd };

Exercises/6-calculate.js

@@ -16,12 +16,23 @@
 Call functions `square` and `cube` in loop, then pass their
 results to function `average`. Print what `average` returns. */
 
-const square = null;
 
-const cube = null;
+const square = (x) => x * x;
 
-const average = null;
+const cube = (x) => x ** 3;
 
-const calculate = null;
+const average = (a, b) => (a + b) / 2;
+
+function calculate() {
+  const arr = [];
+
+  for (let i = 0; i <= 9; i++) {
+    const result = average(square(i), cube(i));
+    // console.log(result);
+    arr.push(result);
+  }
+
+  return arr;
+}
 
 module.exports = { square, cube, average, calculate };

Exercises/7-objects.js

@@ -7,6 +7,17 @@
 - Try to assign other object to both identifiers.
 - Explain script behaviour. */
 
-const fn = null;
+const fn = function() {
+  // Init objects
+  const obj1 = { name: 'Linus', };
+  let obj2 = { name: 'Satochi' };
+
+  // Just change value of field `name`
+  obj1.name = 'Richard';
+  obj2.name = 'Vitalik';
+
+  // Obj1 is a variable we can change data in it
+  obj2 = { name: 'Lennart' };
+};
 
 module.exports = { fn };

Exercises/8-create.js

@@ -5,6 +5,6 @@
   Example: `createUser('Marcus Aurelius', 'Roma')`
   will return object `{ name: 'Marcus Aurelius', city: 'Roma' }` */
 
-const createUser = null;
+const createUser = (name, city) => ({ name, city });
 
 module.exports = { createUser };

Exercises/9-array.js

@@ -9,8 +9,16 @@ Object example: `{ name: 'Marcus Aurelius', phone: '+380445554433' }`.
 `findPhoneByName(name: string): string`. Returning phone from that object
 where field `name` equals argument `name`. Use `for` loop for this search. */
 
-const phonebook = null;
+const phonebook = [
+  { name: 'Linus Torvalds', phone: '+38056323498' },
+  { name: 'Richard Stallman', phone: '+3808384834' },
+  { name: 'Eugen Rochko', phone: '+380734190748' },
+];
 
-const findPhoneByName = null;
+const findPhoneByName = (name) => {
+  for (const record of phonebook) {
+    if (record.name === name) return record;
+  }
+};
 
 module.exports = { phonebook, findPhoneByName };

Exercises/a-hash.js

@@ -7,8 +7,12 @@ contains `phone`.
 `findPhoneByName(name: string): string`. Returning phone from hash/object.
 Use `hash[key]` to find needed phone. */
 
-const phonebook = null;
+const phonebook = {
+  linus: '+38056323498',
+  richard: '+3808384834',
+  eugen: '+380734190748',
+};
 
-const findPhoneByName = null;
+const findPhoneByName = (name) => phonebook[name];
 
 module.exports = { phonebook, findPhoneByName };