From b1f81c30b24b5ba9fd2e21f5252114934a35d5c8 Mon Sep 17 00:00:00 2001
From: vfonsah <vitalis.fonsah@gmail.com>
Date: Sun, 6 Sep 2020 23:35:05 +0100
Subject: [PATCH] calculator & palindromes projects

---
 calculator/calculator.js   | 56 +++++++++++++++++++++++++-------------
 palindromes/palindromes.js | 17 ++++++++++--
 2 files changed, 51 insertions(+), 22 deletions(-)

diff --git a/calculator/calculator.js b/calculator/calculator.js
index 2d904a8..e369e59 100644
--- a/calculator/calculator.js
+++ b/calculator/calculator.js
@@ -1,32 +1,50 @@
-function add () {
-	
+function add(a, b) {
+  return a + b;
 }
 
-function subtract () {
-	
+function subtract(a, b) {
+  return a - b;
 }
 
-function sum () {
-	
+function sum(arr) {
+  let sum = 0;
+  arr.forEach((num) => {
+    sum += num;
+  });
+
+  return arr.length == 0 ? 0 : sum;
 }
 
-function multiply () {
-	
+function multiply(arr) {
+	let product = 1;
+  arr.forEach((num) => {
+    product *= num;
+  });
+
+  return arr.length == 0 ? 0 : product;
 }
 
-function power() {
-	
+function power(num, pow) {
+	let exponent = 1
+	for (let i = 0; i < pow; i++) {
+		exponent *= num;		
+	}
+	return exponent;
 }
 
-function factorial() {
-	
+function factorial(n) {
+	let facto = 1;
+	for (let i = 0; i < n; i++) {
+		facto = n * factorial(n-1);		
+	}
+	return n == 0 || n == 1 ? 1 : facto;
 }
 
 module.exports = {
-	add,
-	subtract,
-	sum,
-	multiply,
-    power,
-	factorial
-}
\ No newline at end of file
+  add,
+  subtract,
+  sum,
+  multiply,
+  power,
+  factorial,
+};
diff --git a/palindromes/palindromes.js b/palindromes/palindromes.js
index ccfda4b..9366793 100644
--- a/palindromes/palindromes.js
+++ b/palindromes/palindromes.js
@@ -1,5 +1,16 @@
-const palindromes = function() {
+const palindromes = function (str) {
+  let strippedStr = str.toLowerCase().replace(
+    /(~|`|!|@|#|$|%|^|&|\*|\(|\)|{|}|\[|\]|;|:|\"|'|<|,|\.|>|\?|\/|\\|\||-|_|\+| |=)/g,
+    ""
+  );
+  let splitStr = strippedStr.split("");
+  let reversedStr = [];
 
-}
+  for (let i = splitStr.length - 1; i >= 0; i--) {
+    reversedStr.push(splitStr[i]);
+  }
+//  return [splitStr, reversedStr, JSON.stringify(splitStr), JSON.stringify(reversedStr)];
+  return JSON.stringify(splitStr) === JSON.stringify(reversedStr) ? true : false;
+};
 
-module.exports = palindromes
+module.exports = palindromes;