* fix: move "Explore Differences Between..." to basic JS, update seed and tests * fix: resequence "Declare String Variables" * fix: move "Declare a Read-Only Variable..." to basic JS, update seed and tests * fix: revert changes to non-English "Explore Differences Between..." test text * fix: revert test strings, solutions, and seeds for non-English challenges * fix: update "Declare String Variables" description * fix: sync quotation marks in description and seed * fix: modify note in "Declare a Read-Only..." challenge * fix: update operator and compound assignment challenges * fix: update string challenges * fix: update array and array method challenges * fix: update function and scope challenges, resequence slightly * fix: "Word Blanks" solution * fix: add spacing to seed * fix: concatenating += challenge spacing * fix: appending variables to strings spacing * fix: find the length of a string spacing * fix: removed instances of removedFromMyArray = 0 * fix: switch challenges * fix: function argument and param spacing * fix: update counting cards, object challenges, and record collection * fix: finish rest of Basic JS section * fix: introducing else statements solution * fix: update spacing and wording * fix: update wording for const challenge * fix: update functional programming challenges * fix: intermediate algorithms and cert challenges * fix: revert some spacing and remove comments for fp challenge solutions * feat: add notes with links to moved let and const challenges in first two es6 challenges * fix: update es6 intro text * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/concatenating-strings-with-the-plus-equals-operator.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/finding-a-remainder-in-javascript.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/global-scope-and-functions.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/functional-programming/implement-map-on-a-prototype.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/declare-a-read-only-variable-with-the-const-keyword.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * fix: concatenating strings with plus operator seed * fix: add comments back to Declare a Read-Only Variable... seed * feat: add es6 to basic javascript redirect tests for let and const challenges * fix: revert "Concatenating Strings with Plus Operator" seed * fix: move test file to cypress/integration/learn/redirects, separate redirect tests Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>
1.9 KiB
id, title, challengeType, videoUrl, forumTopicId, dashedName
id | title | challengeType | videoUrl | forumTopicId | dashedName |
---|---|---|---|---|---|
5675e877dbd60be8ad28edc6 | Iterate Through an Array with a For Loop | 1 | https://scrimba.com/c/caeR3HB | 18216 | iterate-through-an-array-with-a-for-loop |
--description--
A common task in JavaScript is to iterate through the contents of an array. One way to do that is with a for
loop. This code will output each element of the array arr
to the console:
const arr = [10, 9, 8, 7, 6];
for (let i = 0; i < arr.length; i++) {
console.log(arr[i]);
}
Remember that arrays have zero-based indexing, which means the last index of the array is length - 1
. Our condition for this loop is i < arr.length
, which stops the loop when i
is equal to length
. In this case the last iteration is i === 4
i.e. when i
becomes equal to arr.length - 1
and outputs 6
to the console. Then i
increases to 5
, and the loop terminates because i < arr.length
is false
.
--instructions--
Declare and initialize a variable total
to 0
. Use a for
loop to add the value of each element of the myArr
array to total
.
--hints--
total
should be declared and initialized to 0.
assert(code.match(/(var|let|const)\s*?total\s*=\s*0.*?;?/));
total
should equal 20.
assert(total === 20);
You should use a for
loop to iterate through myArr
.
assert(/for\s*\(/g.test(code) && /myArr\s*\[/g.test(code));
You should not attempt to directly assign the value 20 to total
.
assert(!__helpers.removeWhiteSpace(code).match(/total[=+-]0*[1-9]+/gm));
--seed--
--after-user-code--
(function(){if(typeof total !== 'undefined') { return "total = " + total; } else { return "total is undefined";}})()
--seed-contents--
// Setup
const myArr = [2, 3, 4, 5, 6];
// Only change code below this line
--solutions--
const myArr = [2, 3, 4, 5, 6];
let total = 0;
for (let i = 0; i < myArr.length; i++) {
total += myArr[i];
}