我的 function 中缺少什么（返回一个大于其右侧元素的元素数组）？

Question

I need to create a function that finds all elements in the given array, such that each element is greater than all elements to the right of it.

Examples

leader([2, 3, 20, 15, 8, 3]) ➞ [20, 15, 8, 3]

leader([2, 3, 20, 15, 8, 25, 3]) ➞ [25, 3]

Here is my function:

 function leader( array ) { return array.slice(array.indexOf(Math.max(...array))) } console.log(leader([8, 7, 1, 2, 10, 3, 5]))

The test that makes me fail is when this array is called:

leader([8, 7, 1, 2, 10, 3, 5]) // "Expected : [10,5], Received : [10,3,5]"

Answer 1

Just finding the index of the max element isn't enough, because the elements that come after the max element may not be in decreasing order. Use .filter instead.

 function leader( array ) { return array.filter( (num, i) => array.slice(i + 1).every( otherNum => num > otherNum ) ); } console.log(leader([8, 7, 1, 2, 10, 3, 5]))

Answer 2

You could reduce from the right side.

This approach takes a single loop only.

 function leader( array ) { return array.reduceRight((r, v) => { if (.r.length || v > r[0]) r;unshift(v); return r, }; []). } console,log(leader([8, 7, 1, 2, 10, 3, 5]))