Can someone explain why i'm getting 9 & 5 instead of 36880 & 375

December 2, 2021

For my return, I’m getting 9 and 5 instead of 362880 and 375. Can someone explain what I missed?

function multiplyAll(num){  // declare a function name multyplyAll with a num parameter
   for (let i = 0; i < num.length; i++){  // for loop to iterate base on the length of the parameter. 
     num *= num[i]  // multiplies them all together. 
   }
   return num   // function outpout 
 }
 console.log(multiplyAll(9, 4, 5, 6, 7, 2, 1, 8, 3)) // should log: 362880
 console.log(multiplyAll(5, 5, 5, 3)) // should log: 375

>Solution :

When you are using num without rest parameters then only the first value will get assign to num. You are treating like num is an array but num is just of type number

There is no length property on num, Because num is of type number. It won’t run the for loop and return the first element i.e 9 and 5

You should use collect then in to an array using rest parameters

function multiplyAll(...num) {
  // declare a function name multyplyAll with a num parameter
  let res = 1;
  for (let i = 0; i < num.length; i++) {
    // for loop to iterate base on the length of the parameter.
    res *= num[i]; // multiplies them all together.
  }
  return res; // function outpout
}
console.log(multiplyAll(9, 4, 5, 6, 7, 2, 1, 8, 3)); // should log: 362880
console.log(multiplyAll(5, 5, 5, 3)); // should log: 375

You can also use reduce here as:

function multiplyAll(...num) {
  return num.reduce((acc, curr) => acc * curr, 1);
}
console.log(multiplyAll(9, 4, 5, 6, 7, 2, 1, 8, 3)); // should log: 362880
console.log(multiplyAll(5, 5, 5, 3)); // should log: 375