Factorialize a Number - How can I do this using reduce()?

Factorialize a Number - How can I do this using reduce()?
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#1

Tell us what’s happening:
How can I do this using reduce()?
If I can use the for loop and decrement the num till it is === to 1 and assign it to an array then use reduce() will it work?
I can’t do it so I’m asking to show me the code if it can be done.

Your code so far

function factorialize(num) {
  if(num === 0 || num === 1){
    return 1;
  }
  
  for(var i = num-1; i >= 1; i-- ){
    num*=i;
  }
  
  return num;
}

factorialize(5);

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Link to the challenge:


#2

Here’s two approaches using reduce.

function factorialize(num) {
  var arr = []
  
  while(num > 0) {
    arr.push(num--)
  }

  return arr.reduce((accumulator, current) => {
    return accumulator * current;
  });
}
function factorialize(num) {
  return Array.apply(null, Array(num)).map((current, index) => {
    return index + 1;
  }).reduce((accumulator, current) => {
    return accumulator * current;
  });
}

#3

Both of the above solutions fail for factorialize(0).

const factorialize = n => n === 0 ? 1 : Array.from(new Array(n),(_,idx) => idx+1)
  .reduce((prod, val) => prod*val);