Scope of variable inside for loop

Question

This function returns the total from an array, and it works perfectly. But if i initialize total inside the for loop, it does not return the sum. Can you please tell me why?

function sum(arr) {
 var total=0;
 for (var i=0;i<arr.length;i++){
 total += arr[i];
 }
 return total;
}

• rdp: When you initialize a variable inside the loop, you are creating a new variable with the assigned value every time. Hence the previous value is lost.

Answer 1

If you initialize it inside the loop, then the initialization happens on each iteration. I would use the word "reinitialize" in fact. I mean, it's just basic control flow — you initialize an accumulator variable before the loop begins, and then you modify it on each iteration of the loop.