8ee50178f3
Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
925 B
925 B
initializeArrayWithRangeRight
Initializes an array containing the numbers in the specified range (in reverse) where start and end are inclusive with their common difference step.
Use Array.from(Math.ceil((end+1-start)/step)) to create an array of the desired length(the amounts of elements is equal to (end-start)/step or (end+1-start)/step for inclusive end), Array.prototype.map() to fill with the desired values in a range.
You can omit start to use a default value of 0.
You can omit step to use a default value of 1.
const initializeArrayWithRangeRight = (end, start = 0, step = 1) =>
Array.from({ length: Math.ceil((end + 1 - start) / step) }).map(
(v, i, arr) => (arr.length - i - 1) * step + start
);
initializeArrayWithRangeRight(5); // [5,4,3,2,1,0]
initializeArrayWithRangeRight(7, 3); // [7,6,5,4,3]
initializeArrayWithRangeRight(9, 0, 2); // [8,6,4,2,0]