Cash Register loss of precision

JavaScript
1

Tell us what’s happening:
the pennies element is supposed to be .04 but it returns .03. how do I compensate for the loss in precision?

Your code so far


function checkCashRegister(price, cash, cid) {
  var status = {
    status:"",
    change:[]
  
  };
  var currency = {
      "ONE HUNDRED":100,
      "TWENTY":20,
      "TEN":10,
      "FIVE":5,
      "ONE":1,
      "QUARTER":.25,
      "DIME":.1,
      "NICKEL":.05,
      "PENNY":.01
  }
  var change=cash-price;
  var times=0;
  var label="";
  var billNum =0;
  var drawerAmnt=0;
  var count=0;

  // Here is your change, ma'am.
  for(var i=cid.length-1;i>=0;i--){
    drawerAmnt+=cid[i][1];
    billNum = currency[cid[i][0]];
    times=Math.floor(change/currency[cid[i][0]]);
    label=cid[i][0];
    if(billNum<=change||cid[i][1]==0){
        
       for(var j=0;j<times;j++){
         if(count<cid[i][1]){
           count+=billNum;
         }

       }

        
         
        
          status.change.unshift([label, Math.round(count * 100) / 100]);
          if(cid[i][1]!=0){
            drawerAmnt-=times*billNum;
          }
          
          change-=count;
          count=0;
    }

  }
   if(change>.1){
       status.status = "INSUFFICIENT_FUNDS";
       status.change = [];
   }else if(drawerAmnt==0){
          status.status="CLOSED";
        }else{
           status.status="OPEN";
        }


  if(status.status==""){
   
  }
  
             
              
  
  
  return status;
}

// Example cash-in-drawer array:
// [["PENNY", 1.01],
// ["NICKEL", 2.05],
// ["DIME", 3.1],
// ["QUARTER", 4.25],
// ["ONE", 90],
// ["FIVE", 55],
// ["TEN", 20],
// ["TWENTY", 60],
// ["ONE HUNDRED", 100]]

console.log(checkCashRegister(3.26, 100, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.1], ["QUARTER", 4.25], ["ONE", 90], ["FIVE", 55], ["TEN", 20], ["TWENTY", 60], ["ONE HUNDRED", 100]]));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.132 Safari/537.36.

Link to the challenge:

2

Always do the calculations in cents, not dollars.

1 Like
3

take a look at this video, it will explain the issue pretty well

2 Likes
4

thank you very much:)

5

thank you, I learned a lot form the video:)