code debugger:the Array.split() function split ‘foo-the’ to [‘the’] but not [‘foo’,’the’]

let see line 81,the value of words is ‘foo-the’

and step next see line 69,split ‘foot-the’ with ‘-‘ ,it turns out ‘the’

the problem comes from when solving the leetcode algorithm question
description :
You are given a string s and an array of strings words of the same length. Return all starting indices of substring(s) in s that is a concatenation of each word in words exactly once, in any order, and without any intervening characters.

You can return the answer in any order.

full code as follows:

 var s = "barfoofoobarthefoobarman"

var words = ["bar", "foo", "the"]
var arr = []
var position = []

function dfs(index, temp, words) {

    var wordsP = words.split('-')

    if (wordsP.length) {
       temp = temp.concat(wordsP[index])
        wordsP.splice(index, 1)
    }
    if (!wordsP.length) {
        arr.push(temp)
        return;

    }

    for (var i = 0; i < words.length; i++) {
        dfs(i, temp, wordsP.join('-'))
    }
}

for (k = 0; k < words.length; k++) {
    dfs(k, '', words.join('-'))
}
//
arr.forEach((item) => {
    if (s.indexOf(item) != -1) {
        position.push(s.indexOf(item))
    }

})