Saving initial copy of array please help

JavaScript
1

So I am trying to save initial copy of cid into variable initialCid. I found one method Array.from() that does a deepcopy. Why isn’t this working when I assign initialCid to cid? initialCid also changes by the time Program reaches at result = initialCid; Please someone help.

function checkCashRegister(price, cash, cid) {
  let change = cash - price;
  let totalCid = 0;
  const initialCid = Array.from(cid);//save deep copy!!!!!!!!!!HELP!!!!!!!!!!!!!!!!!
  let currencyUnit = [["PENNY", 0.01], ["NICKEL", 0.5], ["DIME", 0.1], ["QUARTER", 0.25], ["ONE", 1.0], ["FIVE", 5.0], ["TEN", 10.0], ["TWENTY", 20.0], ["ONE HUNDRED", 100.0]];
  
  let count = 0;
  let result = [];
  let status = "";
  let initialChange = change;
  
  for(let i = 0;i < cid.length;i++){
    totalCid += cid[i][1];
  }
  if (change > totalCid) {
    return {status: "INSUFFICIENT_FUNDS", change: []};
  }
  //console.log(change);
  //find how many times we can subtract
  for(let i = 0;i < cid.length;i++){
    cid[i][2] = cid[i][1] / currencyUnit[i][1];
  }
  
  for(let i = currencyUnit.length-1;(i >= 0);i--){
   
    if(change >= currencyUnit[i][1]){
      
      //if 3rd array value 
      
      while((count < cid[i][2])&&(change >= 0)&&(change >=currencyUnit[i][1])){
        change = Math.round(change*100)/100;
        cid[i][1] = Math.round(cid[i][1]*100)/100;
        //console.log("change = ",change,", i = ",i,", count = ",count,", cid[i][2] = ",cid[i][2],", cid[i][1] = ",cid[i][1]);
        change -= currencyUnit[i][1];
        cid[i][1] -= currencyUnit[i][1];        
        count++;
        
      }
      
      //console.log(change, cid[i][1],i);
      result.push([cid[i][0],currencyUnit[i][1]*count]);
      //check in cid how many times we can subtract;
      
      
    }
    count = 0;
  }
  
  if(change != 0){
    return {status: "INSUFFICIENT_FUNDS", change: []};
  }
  //console.log(change + " total " + totalCid);
  if (change !== 0){
    status = "INSUFFICIENT_FUNDS";
    result = [];
  } else if ((change === 0)&&(initialChange === totalCid)){
    status = "CLOSED";    
    result = initialCid;//!!!!!!!!!!!!HELP!!!!!!!!!!!!!!!!
  }
  else{
    status = "OPEN";
  }
  
  return {status: status, change: result};
}

console.log(checkCashRegister(19.5, 20, [["PENNY", 0.5], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]));
2

Hi, what is the expected behavior of your program ? because if I console log cid at the beginning it gives the exact same result cid[9][3]

3

Hi
At the top it should give
initialCid = [[“PENNY”, 0.5], [“NICKEL”, 0], [“DIME”, 0], [“QUARTER”, 0], [“ONE”, 0], [“FIVE”, 0], [“TEN”, 0], [“TWENTY”, 0], [“ONE HUNDRED”, 0]]
which it does
but I want it to keep this value when I reach

else if ((change === 0)&&(initialChange === totalCid)){
    status = "CLOSED";    
    result = initialCid;//!!!!!!!!!!!!HELP!!!!!!!!!!!!!!!!
  }
  else{
    status = "OPEN";
  }
  
  return {status: status, change: result};

so the output of initialCid should be what Cid was when function started
initialCid should be
[[“PENNY”, 0.5], [“NICKEL”, 0], [“DIME”, 0], [“QUARTER”, 0], [“ONE”, 0], [“FIVE”, 0], [“TEN”, 0], [“TWENTY”, 0], [“ONE HUNDRED”, 0]]

4

Capture
Here is what it gave at the top

5 
let initialCid = [];//save deep copy!!!!!!!!!!HELP!!!!!!!!!!!!!!!!!
  for (let i=0;i<cid.length;i++)
	initialCid[i] = Array.from(cid[i])

Apparently u can’t copy an array of arrays

1 Like
6

One option is to use JSON.parse/JSON.stringify.

const initialCid = JSON.parse(JSON.stringify(cid));

1 Like
7

I don’t see the problem

function checkCashRegister(cid) {
const initialCid = Array.from(cid);//save shallow copy
alert('cid = '+cid);
cid[0]=['wwwwwwwwwwwwwwwwwww',9];
alert('cid = '+cid);
alert('initialCid = '+initialCid);
}
checkCashRegister([["PENNY", 0.5], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]])
8

Try running the code from the first post on the challenge. Then try it with a deep copy.

9

JSON method worked for me. I couldn’t figure out how to keep a separate copy of cid array.
Thank you guys for your help.

10

I provided you with a solution without JSON method …

1 Like
11

In case you missed here you go again

let initialCid = [ ];//save deep copy!!!HELP!!!
for (let i=0;i<cid.length;i++)
initialCid[i] = Array.from(cid[i])
12

Thank you
Appreciate your help and time.

13

You’re welcome good luck

14

@ratid

When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

You can also use the “preformatted text” tool in the editor (</>) to add backticks around text.

Pre-formatted-text
Pre-formatted-text1356×380 401 KB

See this post to find the backtick on your keyboard.
Note: Backticks (`) are not single quotes (’).

15

@lasjorg thanks for letting me know, will do next time
it’s better this way

16

No problem, you can always edit your posts. It helps other people reading the thread if they are able to read the code better.

1 Like