Can you help me I want to print the value of factorial 4 but the following function is always giving NAN why?

Question

My question is about recursive function why it is showing always NAN instead of showing the value of factorial 4.

function factorial(i){
              if (i == 1) { return;}  
              return i * factorial(--i);};        
      console.log(factorial(4));

Answer 1

function factorial(i){
              if (i == 1) { return 1;}  
              return i * factorial(--i);};        
      console.log(factorial(4));

Answer 2

if (i == 1) { return;} you should return number hear like return 1;

function factorial(i){
              if (i == 1) { return 1;}  
              return i * factorial(--i);};        
      console.log(factorial(4));