4.2 KiB
4.2 KiB
id, title, challengeType, videoUrl, localeTitle
id | title | challengeType | videoUrl | localeTitle |
---|---|---|---|---|
587d7b7b367417b2b2512b15 | Iterate Through All an Array's Items Using For Loops | 1 | 使用for循环遍历所有数组的项目 |
Description
every()
, forEach()
, map()
等),但是这种技术最灵活并且为我们提供了最大的控制量是一个简单的for
循环。考虑以下: function greaterThanTen(arr){使用
让newArr = [];
for(let i = 0; i <arr.length; i ++){
if(arr [i]> 10){
(ARR [I])newArr.push;
}
}
返回newArr;
}
greaterThanTen([2,12,8,14,80,0,1]);
//返回[12,14,80]
for
循环,此函数遍历并访问数组的每个元素,并使其经受我们创建的简单测试。通过这种方式,我们可以轻松地以编程方式确定哪些数据项大于10
,并返回包含这些项的新数组。 Instructions
filteredArray
,它接受arr
,一个嵌套数组和elem
作为参数,并返回一个新数组。 elem
表示在arr
嵌套的一个或多个数组上可能存在或不存在的元素。使用for
循环修改函数,以返回已传递数组的过滤版本,以便删除嵌套在包含elem
arr
中的任何数组。 Tests
tests:
- text: '<code>filteredArray([[10, 8, 3], [14, 6, 23], [3, 18, 6]], 18)</code>应该返回<code>[ [10, 8, 3], [14, 6, 23] ]</code>'
testString: 'assert.deepEqual(filteredArray([ [10, 8, 3], [14, 6, 23], [3, 18, 6] ], 18), [[10, 8, 3], [14, 6, 23]], "<code>filteredArray([[10, 8, 3], [14, 6, 23], [3, 18, 6]], 18)</code> should return <code>[ [10, 8, 3], [14, 6, 23] ]</code>");'
- text: '<code>filteredArray([ ["trumpets", 2], ["flutes", 4], ["saxophones", 2] ], 2)</code>应返回<code>[ ["flutes", 4] ]</code>'
testString: 'assert.deepEqual(filteredArray([ ["trumpets", 2], ["flutes", 4], ["saxophones", 2] ], 2), [["flutes", 4]], "<code>filteredArray([ ["trumpets", 2], ["flutes", 4], ["saxophones", 2] ], 2)</code> should return <code>[ ["flutes", 4] ]</code>");'
- text: '<code>filteredArray([ ["amy", "beth", "sam"], ["dave", "sean", "peter"] ], "peter")</code>应该返回<code>[ ["amy", "beth", "sam"] ]</code>'
testString: 'assert.deepEqual(filteredArray([["amy", "beth", "sam"], ["dave", "sean", "peter"]], "peter"), [["amy", "beth", "sam"]], "<code>filteredArray([ ["amy", "beth", "sam"], ["dave", "sean", "peter"] ], "peter")</code> should return <code>[ ["amy", "beth", "sam"] ]</code>");'
- text: '<code>filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3)</code>应该返回<code>[ ]</code>'
testString: 'assert.deepEqual(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3), [], "<code>filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3)</code> should return <code>[ ]</code>");'
- text: <code>filteredArray</code>函数应该使用<code>for</code>循环
testString: 'assert.notStrictEqual(filteredArray.toString().search(/for/), -1, "The <code>filteredArray</code> function should utilize a <code>for</code> loop");'
Challenge Seed
function filteredArray(arr, elem) {
let newArr = [];
// change code below this line
// change code above this line
return newArr;
}
// change code here to test different cases:
console.log(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3));
Solution
// solution required