Task core-js

src/01-strings-tasks.js

@@ -18,11 +18,10 @@
  *   'aa',''    => 'aa'
  *   '',  'bb'  => 'bb'
  */
-function concatenateStrings(/* value1, value2 */) {
-  throw new Error('Not implemented');
+function concatenateStrings(value1, value2) {
+  return value1 + value2;
 }
 
-
 /**
  * Returns the length of given string.
  *
@@ -34,10 +33,11 @@ function concatenateStrings(/* value1, value2 */) {
  *   'b'     => 1
  *   ''      => 0
  */
-function getStringLength(/* value */) {
-  throw new Error('Not implemented');
+function getStringLength(value) {
+  return value.length;
 }
 
+
 /**
  * Returns the result of string template and given parameters firstName and lastName.
  * Please do not use concatenation, use template string :
@@ -51,8 +51,8 @@ function getStringLength(/* value */) {
  *   'John','Doe'      => 'Hello, John Doe!'
  *   'Chuck','Norris'  => 'Hello, Chuck Norris!'
  */
-function getStringFromTemplate(/* firstName, lastName */) {
-  throw new Error('Not implemented');
+function getStringFromTemplate(firstName, lastName) {
+  return `Hello, ${firstName} ${lastName}!`;
 }
 
 /**
@@ -65,8 +65,8 @@ function getStringFromTemplate(/* firstName, lastName */) {
  *   'Hello, John Doe!' => 'John Doe'
  *   'Hello, Chuck Norris!' => 'Chuck Norris'
  */
-function extractNameFromTemplate(/* value */) {
-  throw new Error('Not implemented');
+function extractNameFromTemplate(value) {
+  return value.slice(7, -1);
 }
 
 
@@ -80,8 +80,8 @@ function extractNameFromTemplate(/* value */) {
  *   'John Doe'  => 'J'
  *   'cat'       => 'c'
  */
-function getFirstChar(/* value */) {
-  throw new Error('Not implemented');
+function getFirstChar(value) {
+  return value.charAt(0);
 }
 
 /**
@@ -95,8 +95,8 @@ function getFirstChar(/* value */) {
  *   'cat'              => 'cat'
  *   '\tHello, World! ' => 'Hello, World!'
  */
-function removeLeadingAndTrailingWhitespaces(/* value */) {
-  throw new Error('Not implemented');
+function removeLeadingAndTrailingWhitespaces(value) {
+  return value.trim();
 }
 
 /**
@@ -110,8 +110,8 @@ function removeLeadingAndTrailingWhitespaces(/* value */) {
  *   'A', 5  => 'AAAAA'
  *   'cat', 3 => 'catcatcat'
  */
-function repeatString(/* value, count */) {
-  throw new Error('Not implemented');
+function repeatString(value, count) {
+  return value.repeat(count);
 }
 
 /**
@@ -126,8 +126,8 @@ function repeatString(/* value, count */) {
  *   'I like legends', 'end' => 'I like legs',
  *   'ABABAB','BA' => 'ABAB'
  */
-function removeFirstOccurrences(/* str, value */) {
-  throw new Error('Not implemented');
+function removeFirstOccurrences(str, value) {
+  return str.replace(value, '');
 }
 
 /**
@@ -141,8 +141,8 @@ function removeFirstOccurrences(/* str, value */) {
  *   '<span>' => 'span'
  *   '<a>' => 'a'
  */
-function unbracketTag(/* str */) {
-  throw new Error('Not implemented');
+function unbracketTag(str) {
+  return str.replace(/[{< >}]/g, '');
 }
 
 
@@ -156,8 +156,8 @@ function unbracketTag(/* str */) {
  *   'Thunderstruck' => 'THUNDERSTRUCK'
  *  'abcdefghijklmnopqrstuvwxyz' => 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
  */
-function convertToUpperCase(/* str */) {
-  throw new Error('Not implemented');
+function convertToUpperCase(str) {
+  return str.toUpperCase();
 }
 
 /**
@@ -175,8 +175,8 @@ function convertToUpperCase(/* str */) {
  *   ],
  *   '[email protected]' => ['[email protected]']
  */
-function extractEmails(/* str */) {
-  throw new Error('Not implemented');
+function extractEmails(str) {
+  return str.match(/([a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9_-]+)/gi);
 }
 
 /**
@@ -202,8 +202,11 @@ function extractEmails(/* str */) {
  *             '└──────────┘\n'
  *
  */
-function getRectangleString(/* width, height */) {
-  throw new Error('Not implemented');
+function getRectangleString(width, height) {
+  const head = `┌${'─'.repeat(width - 2)}┐\n`;
+  const midle = `│${' '.repeat(width - 2)}│\n`;
+  const foot = `└${'─'.repeat(width - 2)}┘\n`;
+  return head + midle.repeat(height - 2) + foot;
 }
 
 
@@ -223,8 +226,10 @@ function getRectangleString(/* width, height */) {
  *    => 'NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm'
  *
  */
-function encodeToRot13(/* str */) {
-  throw new Error('Not implemented');
+function encodeToRot13(str) {
+  const originalAlpha = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
+  const cipher = 'nopqrstuvwxyzabcdefghijklmNOPQRSTUVWXYZABCDEFGHIJKLM';
+  return str.replace(/[a-z]/gi, (letter) => cipher[originalAlpha.indexOf(letter)]);
 }
 
 /**
@@ -240,11 +245,10 @@ function encodeToRot13(/* str */) {
  *   isString('test') => true
  *   isString(new String('test')) => true
  */
-function isString(/* value */) {
-  throw new Error('Not implemented');
+function isString(value) {
+  return typeof value === 'string' || value instanceof String;
 }
 
-
 /**
  * Returns playid card id.
  *
@@ -269,11 +273,14 @@ function isString(/* value */) {
  *   'Q♠' => 50
  *   'K♠' => 51
  */
-function getCardId(/* value */) {
-  throw new Error('Not implemented');
+function getCardId(value) {
+  const arrCards = ['A♣', '2♣', '3♣', '4♣', '5♣', '6♣', '7♣', '8♣', '9♣', '10♣', 'J♣', 'Q♣', 'K♣',
+    'A♦', '2♦', '3♦', '4♦', '5♦', '6♦', '7♦', '8♦', '9♦', '10♦', 'J♦', 'Q♦', 'K♦',
+    'A♥', '2♥', '3♥', '4♥', '5♥', '6♥', '7♥', '8♥', '9♥', '10♥', 'J♥', 'Q♥', 'K♥',
+    'A♠', '2♠', '3♠', '4♠', '5♠', '6♠', '7♠', '8♠', '9♠', '10♠', 'J♠', 'Q♠', 'K♠'];
+  return arrCards.indexOf(value);
 }
 
-
 module.exports = {
   concatenateStrings,
   getStringLength,

src/02-numbers-tasks.js

@@ -19,8 +19,8 @@
  *   5, 10 => 50
  *   5, 5  => 25
  */
-function getRectangleArea(/* width, height */) {
-  throw new Error('Not implemented');
+function getRectangleArea(width, height) {
+  return width * height;
 }
 
 
@@ -35,8 +35,8 @@ function getRectangleArea(/* width, height */) {
  *   3.14 => 19.729201864543903
  *   0    => 0
  */
-function getCircleCircumference(/* radius */) {
-  throw new Error('Not implemented');
+function getCircleCircumference(radius) {
+  return 2 * Math.PI * radius;
 }
 
 /**
@@ -51,8 +51,8 @@ function getCircleCircumference(/* radius */) {
  *  10, 0  => 5
  *  -3, 3  => 0
  */
-function getAverage(/* value1, value2 */) {
-  throw new Error('Not implemented');
+function getAverage(value1, value2) {
+  return value1 / 2 + value2 / 2;
 }
 
 /**
@@ -70,8 +70,8 @@ function getAverage(/* value1, value2 */) {
  *   (0,0) (1,0)    => 1
  *   (-5,0) (10,-10) => 18.027756377319946
  */
-function getDistanceBetweenPoints(/* x1, y1, x2, y2 */) {
-  throw new Error('Not implemented');
+function getDistanceBetweenPoints(x1, y1, x2, y2) {
+  return Math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2));
 }
 
 /**
@@ -86,8 +86,8 @@ function getDistanceBetweenPoints(/* x1, y1, x2, y2 */) {
  *   x + 8 = 0       => -8
  *   5*x = 0         => 0
  */
-function getLinearEquationRoot(/* a, b */) {
-  throw new Error('Not implemented');
+function getLinearEquationRoot(a, b) {
+  return -b / a;
 }
 
 
@@ -109,8 +109,16 @@ function getLinearEquationRoot(/* a, b */) {
  *   (0,1) (0,1)     => 0
  *   (0,1) (1,2)     => 0
  */
-function getAngleBetweenVectors(/* x1, y1, x2, y2 */) {
-  throw new Error('Not implemented');
+function getAngleBetweenVectors(x1, y1, x2, y2) {
+  let angle = Math.atan2(x1, y1) - Math.atan2(x2, y2);
+  if (angle < 0) {
+    angle += 2 * Math.PI;
+  }
+  if (angle > Math.PI) {
+    angle -= 2 * Math.PI;
+  }
+
+  return angle;
 }
 
 /**
@@ -125,8 +133,8 @@ function getAngleBetweenVectors(/* x1, y1, x2, y2 */) {
  *     5     => 5
  *     0     => 0
  */
-function getLastDigit(/* value */) {
-  throw new Error('Not implemented');
+function getLastDigit(value) {
+  return value % 10;
 }
 
 
@@ -141,8 +149,8 @@ function getLastDigit(/* value */) {
  *     '37'     => 37
  * '-525.5'     => -525.5
  */
-function parseNumberFromString(/* value */) {
-  throw new Error('Not implemented');
+function parseNumberFromString(value) {
+  return Number(value);
 }
 
 /**
@@ -158,8 +166,8 @@ function parseNumberFromString(/* value */) {
  *   3,3,3   => 5.196152422706632
  *   1,2,3   => 3.741657386773941
  */
-function getParallelepipedDiagonal(/* a, b, c */) {
-  throw new Error('Not implemented');
+function getParallelepipedDiagonal(a, b, c) {
+  return Math.sqrt(a ** 2 + b ** 2 + c ** 2);
 }
 
 
@@ -180,8 +188,8 @@ function getParallelepipedDiagonal(/* a, b, c */) {
  *   1678, 2  => 1700
  *   1678, 3  => 2000
  */
-function roundToPowerOfTen(/* num, pow */) {
-  throw new Error('Not implemented');
+function roundToPowerOfTen(num, pow) {
+  return Math.round(num / 10 ** pow) * (10 ** pow);
 }
 
 /**
@@ -201,8 +209,13 @@ function roundToPowerOfTen(/* num, pow */) {
  *   16 => false
  *   17 => true
  */
-function isPrime(/* n */) {
-  throw new Error('Not implemented');
+function isPrime(n) {
+  for (let i = 2; n > i; i += 1) {
+    if (n % i === 0) {
+      return false;
+    }
+  }
+  return n > 1;
 }
 
 /**
@@ -220,8 +233,8 @@ function isPrime(/* n */) {
  *   toNumber(42, 0) => 42
  *   toNumber(new Number(42), 0) => 42
  */
-function toNumber(/* value, def */) {
-  throw new Error('Not implemented');
+function toNumber(value, def) {
+  return Number(value) || def;
 }
 
 module.exports = {