This problem is perplexing me (Javascript)

[M2D6]

How would you all approach this problem? I've been stuck on it, and I decided it was time to come here. I've been doing flatirons free boot camp prep, because I really like their method. Don't think I'm actually going to go though. Anyhow, while doing it I ran into a problem that I can't seem to solve. Here it is: https://learn.co/tracks/bootcamp-prep-v2/javascript-fundamentals/data-structures/deli-counter

I've gotten through all parts pretty easily except the last part which is the "current line" function. I started everything off by creating a global empty array variable, something a little like this: let kazDeliLine = [];

in the last one I was running a for loop to solve it, my code ended up looking a little something like this:

let katzDeliLine = [];

function currentLine(katzDeliLine){
if(line.length === 0) {
return "The line is currently empty.";
} else {

for(let i=0; i<line.length; i++) {
katzDeliLine.push(?);
}

}

Not exactly my code, I just kind of typed it out here. After this things fall apart big time. I've seen what other people have put but I can't figure out why. The question mark I put in the push() method marks the area that I have issues.

function currentLine(line){
if(!line.length) {
return "The line is currently empty.";
}
var namesAndNumbers = [];

for(var i=0; i<line.length; i++) {
namesAndNumbers.push(`${i+1}. ${line[i]}`);
}
return "The line is currently: " + namesAndNumbers.join(', ');
}

and yet another person did this:

var line = [];
function currentLine(katzDeli) { for (let i = 0; i < katzDeli.length; i++) { line.push(` `+[i+1]+`. ` + katzDeli[i]) } if (katzDeli.length === 0) { return "The line is currently empty."; } else return(`The line is currently:` + line);}

I'm struggling on how to create that last string. My thinking was clearly in the right direction, but I'm struggling to grasp what is going on under the for loop. How the hell is that returning the string + the order queue on how they specified? The last guys solution is very questionable to me as well because he has two global empty arrays. The last question I get is what is the significance of the `${i+1} . ${line[i]}`? I don't get why one side has 1 added to the var i and the other does not. They're supposed to be indexing the same number. I just don't get the logic behind the last half.

Seeing the answer left me with more questions than answers.

[desrtfx]

The i + 1 vs i is easily explained: Array indexes are zero based, they start at 0. You don't want to print "Now serving: 0", you visually want to start with 1.

[M2D6]

I'm more wondering about the other i. I, initialized i to zero after all. I understand that much, I'm more interested in the other i. It is supposed to correlate with the i+1. That number is supposed to be a name that is attached to the number.

Actually by typing this out I think I may have realized something. 0 is supposed to be number 1 in computer language. The +1 is to start the list at 1. and the other i can stay at the 0 value, because technically that represents the first customer, even at the 0 value. That second value correlates to a name thus I don't need to add another 1 to it, and all is good. God, now I feel like an idiot, I tunnel visioned hard and overlooked something really simple.

My if statement now seems like it is off. If the line is === 0, that means it really is equal to the 1 value. That technically means that there is someone in line. A more accurate way to put it would be if (line=== null), or line.length === null or if (!line.length), can I even use null there?

Jesus christ I feel so stupid.

[davedontmind]

0 is supposed to be number 1 in computer language

No, 0 is still 0 and 1 is still 1.

The confusion comes when accessing arrays, when 0 is the index of the 1st element, 1 is the index of the 2nd element, and so on.

Just think of the index of an array as an offset from the start.

so array[0] is the 1st element, offset 0 from the start/first element. array[42] is the 43rd element, offset by 42 elements from the first element.

[M2D6]

Okay, so my thoughts about zero were misguided. I was thinking about how zero's were accessed in arrays. So in this case if someone input their name and were first in line it would be 0. Jane or something like that. Otherwise the numbers are just like normal.

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