Latihan Eloquent Javascript

function factorial(n){
  if(n == 0){
    return 1;
  }else{
    return factorial(n - 1)*n;
  }
}
console.log(factorial(9));
////////////////////////////////////////////////////
var nilai;
switch (nilai = 1){
  case 0 :
    nilai = 1;
    break;
  case 1:
    nilai = 2;
}
console.log(nilai);
/////////////////////////////////////////////////////
let total = 0, count = 1; 
while (count <= 10) { 
  total += count; 
  count += 1; 
}
console.log(total)
//////////////////////////////////////////////////////

var array = [];

function range (arr){  
    var lower = Math.min(arr[0],arr[1]);    
    var upper = Math.max(arr[0],arr[1]);  

    for (var i=lower;i<=upper;i++){  
        array.push(i);  
    }
    return array; // return the array to be used in the sum function
}  

function sum(array){  
    let total = 0; // need to create a variable outside the loop scope
    for(var i in array){  
       total = total+array[i];  
    }
    return total;
}  

console.log(sum(range([1,10])));
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