js_assignment

src/array.js

@@ -11,7 +11,12 @@
  *    [0, 1, 2, 3, 4, 5], 5    => 5
  */
 function findElement(arr, value) {
-	throw new Error("Not implemented");
+	for(let i=0; i < arr.length; i++){
+		if(arr[i]==value){
+			return i;
+		}
+	}
+	return -1;
 }
 
 /**
@@ -27,7 +32,11 @@ function findElement(arr, value) {
  *    [] => []
  */
 function doubleArray(arr) {
-	throw new Error("Not implemented");
+	let k=arr.length;
+	for( let i=0; i < k ; i++){
+		arr[i+k]=arr[i];
+	}
+	return arr;
 }
 
 /**
@@ -42,7 +51,7 @@ function doubleArray(arr) {
  *    [] => []
  */
 function getArrayOfPositives(arr) {
-	throw new Error("Not implemented");
+	return arr.filter(n => n>0);
 }
 
 /**
@@ -59,7 +68,7 @@ function getArrayOfPositives(arr) {
  *    [ false, 0, NaN, '', undefined ]   => [ ]
  */
 function removeFalsyValues(arr) {
-	throw new Error("Not implemented");
+	return arr.filter(Boolean);
 }
 
 /**
@@ -73,7 +82,12 @@ function removeFalsyValues(arr) {
  *    [ 'angular', 'react', 'ember' ] => [ 7, 5, 5 ]
  */
 function getStringsLength(arr) {
-	throw new Error("Not implemented");
+	let k=arr.length;
+	let str=[];
+	for(let i=0;i<arr.length;i++){
+		str[i]=arr[i].length;
+	}
+	return str;
 }
 
 /**
@@ -89,8 +103,12 @@ function getStringsLength(arr) {
  *   [ 1, 10, 100, 1000 ]  => 1111
  */
 function getItemsSum(arr) {
-	throw new Error("Not implemented");
-}
+	let sum=0;
+	for(let i=0;i<arr.length; i++){
+		sum=sum+arr[i];
+	}
+	return sum;
+ }
 
 module.exports = {
 	findElement,

src/conditionalAndLoops.js

@@ -19,7 +19,12 @@
  *
  */
 function getFizzBuzz(num) {
-	throw new Error("Not implemented");
+	if((num%3)!=0 && (num%5)!=0){return num;}
+	else{
+		if((num%3)==0 && (num%5)!=0){return 'Fizz';}
+		else{if((num%3)!=0 && (num%5)==0){return 'Buzz';}
+		else{if((num%3)==0 && (num%5)==0){return 'FizzBuzz';}}}
+	}
 }
 
 /**
@@ -34,7 +39,11 @@ function getFizzBuzz(num) {
  *   10 => 3628800
  */
 function getFactorial(n) {
-	throw new Error("Not implemented");
+	let result=1;
+	for(let i=1 ; i<=n;i++){
+		result=result*i;
+	}
+	return result;
 }
 
 /**
@@ -50,7 +59,12 @@ function getFactorial(n) {
  *   -1,1  =>  0  ( = -1 + 0 + 1 )
  */
 function getSumBetweenNumbers(n1, n2) {
-	throw new Error("Not implemented");
+	let sum=0;
+	for(let i=n1; i<=n2; i++){
+		sum=sum + i;
+	}
+	return sum;
+
 }
 
 /**
@@ -69,7 +83,10 @@ function getSumBetweenNumbers(n1, n2) {
  *   10,10,10 =>  true
  */
 function isTriangle(a, b, c) {
-	throw new Error("Not implemented");
+	if( (a+b)>c && (b+c)>a && (a+c)>b ){
+		return true;
+	}
+	else{return false;}
 }
 
 /**
@@ -85,7 +102,7 @@ function isTriangle(a, b, c) {
  * 'noon' => 'noon'
  */
 function reverseString(str) {
-	throw new Error("Not implemented");
+	return str.split("").reverse().join('');
 }
 
 /**
@@ -109,10 +126,21 @@ function reverseString(str) {
  *   '{)' = false
  *   '{[(<{[]}>)]}' = true
  */
-function isBracketsBalanced(str) {
-	throw new Error("Not implemented");
-}
 
+function isBracketsBalanced(str) {
+		const stack = [];
+		const brackets = {'(': ')', '[': ']', '{': '}', '<': '>'};
+
+		for (const char of str) {
+			if (brackets.hasOwnProperty(char)) {
+				stack.push(char);
+			} else if (brackets[stack.pop()] !== char) {
+				return false;
+			}
+		}
+
+		return stack.length === 0;
+	}
 /**
  * Returns the human readable string of time period specified by the start and end time.
  * The result string should be constrcuted using the folliwing rules:
@@ -145,9 +173,38 @@ function isBracketsBalanced(str) {
  *
  */
 function timespanToHumanString(startDate, endDate) {
-	throw new Error("Not implemented");
-}
-
+const timeDifference = (endDate - startDate) ;
+		const seconds = Math.round(timeDifference / 1000);
+		const minutes = Math.round(timeDifference / (1000*60));
+		const hours = Math.round(timeDifference / (1000*60*60));
+		const days = Math.round(timeDifference / (1000*60*60*24));
+		const months = Math.round(timeDifference / (1000*60*60*24*30));
+		const years = Math.round(timeDifference / (1000*60*60*24*30*12));
+
+		if ( seconds < 45) {
+			return "a few seconds ago";
+		} else if (seconds <= 90) {
+			return "a minute ago";
+		} else if (minutes <= 45) {
+			return `${minutes} minutes ago`;
+		} else if (minutes <= 90) {
+			return "an hour ago";
+		} else if (hours <= 22) {
+			return `${hours} hours ago`;
+		} else if (hours <= 36) {
+			return "a day ago";
+		} else if (days <= 25) {
+			return `${days} days ago`;
+		} else if (days <= 45) {
+			return "a month ago";
+		} else if (days <= 345) {
+			return `${months} months ago`;
+		} else if (days <= 545) {
+			return "a year ago";
+		} else {
+			return `${years} years ago`;
+		}
+	}
 /**
  * Returns the string with n-ary (binary, ternary, etc, where n<=10) representation of
  * specified number.
@@ -169,7 +226,17 @@ function timespanToHumanString(startDate, endDate) {
  *    365, 10 => '365'
  */
 function toNaryString(num, n) {
-	throw new Error("Not implemented");
+
+		if(num==0){
+			return "0";
+		}
+		var toNaryString = "";
+		while(num>0){
+			var remainder=num%n;
+			toNaryString = remainder+toNaryString;
+			num=Math.floor(num/n);
+		}
+		return toNaryString;
 }
 
 module.exports = {

src/numbers.js

@@ -10,7 +10,7 @@
  *   5, 5  => 25
  */
 function getRectangleArea(width, height) {
-	throw new Error("Not implemented");
+	return (width*height);
 }
 
 /**
@@ -26,7 +26,10 @@ function getRectangleArea(width, height) {
  *  -3, 3  => 0
  */
 function getAverage(value1, value2) {
-	throw new Error("Not implemented");
+	var k1 = value1/2;
+	var k2= value2/2;
+	let avg= k1+k2;
+	return avg;
 }
 
 /**
@@ -42,7 +45,8 @@ function getAverage(value1, value2) {
  *   5*x = 0         => 0
  */
 function getLinearEquationRoot(a, b) {
-	throw new Error("Not implemented");
+	if(b==0){return 0;}
+	else{return -(b/a);}
 }
 
 /**
@@ -58,7 +62,8 @@ function getLinearEquationRoot(a, b) {
  *     0     => 0
  */
 function getLastDigit(value) {
-	throw new Error("Not implemented");
+	if(value<0){return (-value)%10;}
+	else{return value%10;}
 }
 
 /**
@@ -73,7 +78,8 @@ function getLastDigit(value) {
  * '-525.5'     => -525.5
  */
 function parseNumberFromString(value) {
-	throw new Error("Not implemented");
+	let num=parseFloat(value);
+	return num;
 }
 
 /**
@@ -94,7 +100,14 @@ function parseNumberFromString(value) {
  *   17 => true
  */
 function isPrime(n) {
-	throw new Error("Not implemented");
+	if( n==2 || n==3)
+	return true;
+	if(n<=1|| n%2 ==0 || n%3 ==0)
+	return false;
+for(let i=5;i*i<=n;i+=6)
+if(n%i==0 || n%(i+2)==0)
+	return false;
+return true;
 }
 
 module.exports = {

src/strings.js

@@ -11,7 +11,7 @@
  *   '',  'bb'  => 'bb'
  */
 function concatenateStrings(value1, value2) {
-	throw new Error("Not implemented");
+	return value1+value2 ;
 }
 
 /**
@@ -26,7 +26,7 @@ function concatenateStrings(value1, value2) {
  *   ''      => 0
  */
 function getStringLength(value) {
-	throw new Error("Not implemented");
+	return value.length;
 }
 
 /**
@@ -40,7 +40,8 @@ function getStringLength(value) {
  *   'cat'       => 'c'
  */
 function getFirstChar(value) {
-	throw new Error("Not implemented");
+	let arr = value.split('');
+	return arr[0];
 }
 
 /**
@@ -55,7 +56,8 @@ function getFirstChar(value) {
  *   '\tHello, World! ' => 'Hello, World!'
  */
 function removeLeadingAndTrailingWhitespaces(value) {
-	throw new Error("Not implemented");
+	let str=value.trim();
+	return str;
 }
 
 /**
@@ -70,7 +72,11 @@ function removeLeadingAndTrailingWhitespaces(value) {
  *   'cat', 3 => 'catcatcat'
  */
 function repeatString(value, count) {
-	throw new Error("Not implemented");
+	let result='';
+	for(let i=0; i<count ; i++){
+		result=result+value;
+	}
+	return result;
 }
 
 /**
@@ -86,7 +92,9 @@ function repeatString(value, count) {
  *   'ABABAB','BA' => 'ABAB'
  */
 function removeFirstOccurrences(str, value) {
-	throw new Error("Not implemented");
+	let index = str.indexOf(value);
+	if(index==-1){return str;}
+	return str.slice(0,index)+str.slice(index+ value.length);
 }
 
 /**
@@ -100,7 +108,7 @@ function removeFirstOccurrences(str, value) {
  *  'abcdefghijklmnopqrstuvwxyz' => 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
  */
 function convertToUpperCase(str) {
-	throw new Error("Not implemented");
+	return str.toUpperCase();
 }
 
 /**
@@ -120,7 +128,10 @@ function convertToUpperCase(str) {
  *
  */
 function encodeToRot13(str) {
-	throw new Error("Not implemented");
+	return str.replace(/[a-zA-Z]/g,function(c){
+		let base=c <= 'Z' ? 65:97;
+		return String.fromCharCode((c.charCodeAt(0)-base+13)%26+base);
+	});
 }
 
 module.exports = {