106 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			106 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | ||
|  | id: 595671d4d2cdc305f0d5b36f | ||
|  | title: Hash from two arrays | ||
|  | challengeType: 5 | ||
|  | forumTopicId: 302283 | ||
|  | dashedName: hash-from-two-arrays | ||
|  | --- | ||
|  | 
 | ||
|  | # --description--
 | ||
|  | 
 | ||
|  | Using two Arrays of equal length, create a Hash object where the elements from one array (the keys) are linked to the elements of the other (the values). | ||
|  | 
 | ||
|  | **Related task:** | ||
|  | 
 | ||
|  | <ul> | ||
|  |   <li><a href='https://rosettacode.org/wiki/Associative arrays/Creation' title='Associative arrays/Creation' target='_blank'>Associative arrays/Creation</a></li> | ||
|  | </ul> | ||
|  | 
 | ||
|  | # --hints--
 | ||
|  | 
 | ||
|  | `arrToObj` should be a function. | ||
|  | 
 | ||
|  | ```js | ||
|  | assert(typeof arrToObj === 'function'); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj([1, 2, 3, 4, 5], ["a", "b", "c", "d", "e"])` should return `{ 1: "a", 2: "b", 3: "c", 4: "d", 5: "e" }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[0]), res[0]); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj([1, 2, 3, 4, 5], ["a", "b", "c", "d"])` should return `{ 1: "a", 2: "b", 3: "c", 4: "d", 5: undefined }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[1]), res[1]); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj([1, 2, 3], ["a", "b", "c", "d", "e"])` should return `{ 1: "a", 2: "b", 3: "c" }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[2]), res[2]); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj(["a", "b", "c", "d", "e"], [1, 2, 3, 4, 5])` should return `{ "a": 1, "b": 2, "c": 3 , "d": 4, "e": 5 }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[3]), res[3]); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj(["a", "b", "c", "d", "e"], [1, 2, 3, 4])` should return `{ "a": 1, "b": 2, "c": 3 , "d": 4, "e": undefined }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[4]), res[4]); | ||
|  | ``` | ||
|  | 
 | ||
|  | `arrToObj(["a", "b", "c"], [1, 2, 3, 4, 5])` should return `{ "a": 1, "b": 2, "c": 3 }` | ||
|  | 
 | ||
|  | ```js | ||
|  | assert.deepEqual(arrToObj(...testCases[5]), res[5]); | ||
|  | ``` | ||
|  | 
 | ||
|  | # --seed--
 | ||
|  | 
 | ||
|  | ## --after-user-code--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | const testCases = [ | ||
|  |   [[1, 2, 3, 4, 5], ['a', 'b', 'c', 'd', 'e']], | ||
|  |   [[1, 2, 3, 4, 5], ['a', 'b', 'c', 'd']], | ||
|  |   [[1, 2, 3], ['a', 'b', 'c', 'd', 'e']], | ||
|  |   [['a', 'b', 'c', 'd', 'e'], [1, 2, 3, 4, 5]], | ||
|  |   [['a', 'b', 'c', 'd', 'e'], [1, 2, 3, 4]], | ||
|  |   [['a', 'b', 'c'], [1, 2, 3, 4, 5]] | ||
|  | ]; | ||
|  | 
 | ||
|  | const res = [ | ||
|  |   { 1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e' }, | ||
|  |   { 1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: undefined }, | ||
|  |   { 1: 'a', 2: 'b', 3: 'c' }, | ||
|  |   { a: 1, b: 2, c: 3, d: 4, e: 5 }, | ||
|  |   { a: 1, b: 2, c: 3, d: 4, e: undefined }, | ||
|  |   { a: 1, b: 2, c: 3 } | ||
|  | ]; | ||
|  | ``` | ||
|  | 
 | ||
|  | ## --seed-contents--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | function arrToObj (keys, vals) { | ||
|  | 
 | ||
|  |   return true; | ||
|  | } | ||
|  | ``` | ||
|  | 
 | ||
|  | # --solutions--
 | ||
|  | 
 | ||
|  | ```js | ||
|  | function arrToObj (keys, vals) { | ||
|  |   return keys.reduce((map, key, index) => { | ||
|  |     map[key] = vals[index]; | ||
|  |     return map; | ||
|  |   }, {}); | ||
|  | } | ||
|  | ``` |