Free Code Camp > Advanced Algorithm Scripting > Exact Change

Exact Change.js

function checkCashRegister(price, cash, cid) {
    var bills = {"PENNY": 0.01, 
                 "NICKEL": 0.05, 
                 "DIME": 0.10, 
                 "QUARTER": 0.25, 
                 "ONE": 1, "FIVE": 5, 
                 "TEN": 10, 
                 "TWENTY": 20, 
                 "ONE HUNDRED": 100};

    var total = function(array) {
        var result = 0;
        for (var i = 0; i < array.length-1; i++) {
            result += array[i][1];
        }
    return result;
    }

    var totalChange = cash - price;
    var totalCID = total(cid);
    var change = [];

    if (totalCID === totalChange)
        return "Closed";

    for (var i = cid.length-1; i >= 0; i--) {
        var numOfBills = Math.floor(totalChange / bills[cid[i][0]]);
        if (numOfBills > 0 && cid[i][1] >= bills[cid[i][0]] * numOfBills) {
            change.push([cid[i][0], bills[cid[i][0]] * numOfBills]);
          // have some problem here
          // in debugger after first run of the next line
          // totalResult is 0 for some reason. What's the reason?
            var totalResult = total(change);
            if (totalResult === totalChange) {
                return change;
            }
        }

    }

    var totalResult = total(change);

    if (totalResult < totalChange)
    return "Insufficient Funds";
}

// Example cash-in-drawer array:
// [["PENNY", 1.01],
// ["NICKEL", 2.05],
// ["DIME", 3.10],
// ["QUARTER", 4.25],
// ["ONE", 90.00],
// ["FIVE", 55.00],
// ["TEN", 20.00],
// ["TWENTY", 60.00],
// ["ONE HUNDRED", 100.00]]


// TESTS

// (typeof checkCashRegister(19.50, 20.00, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.10], ["QUARTER", 4.25], ["ONE", 90.00], ["FIVE", 55.00], ["TEN", 20.00], ["TWENTY", 60.00], ["ONE HUNDRED", 100.00]]) === "array") ? console.log("...OK") : console.log("FAIL: must be type \"array\"");

// (typeof checkCashRegister(19.50, 20.00, [["PENNY", 0.01], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]) === "string") ? console.log("...OK") : console.log("FAIL: must be a string");

// (typeof checkCashRegister(19.50, 20.00, [["PENNY", 0.50], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]) === "string") ? console.log("...OK") : console.log("FAIL: must be a string");

(checkCashRegister(19.50, 20.00, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.10], ["QUARTER", 4.25], ["ONE", 90.00], ["FIVE", 55.00], ["TEN", 20.00], ["TWENTY", 60.00], ["ONE HUNDRED", 100.00]]) === [["QUARTER", 0.50]]) ? console.log("...OK") : console.log("FAIL: must be [[\"QUARTER\", 0.50]]");

// (checkCashRegister(3.26, 100.00, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.10], ["QUARTER", 4.25], ["ONE", 90.00], ["FIVE", 55.00], ["TEN", 20.00], ["TWENTY", 60.00], ["ONE HUNDRED", 100.00]]) === [["TWENTY", 60.00], ["TEN", 20.00], ["FIVE", 15.00], ["ONE", 1.00], ["QUARTER", 0.50], ["DIME", 0.20], ["PENNY", 0.04]]) ? console.log("...OK") : console.log('FAIL: must be [["TWENTY", 60.00], ["TEN", 20.00], ["FIVE", 15.00], ["ONE", 1.00], ["QUARTER", 0.50], ["DIME", 0.20], ["PENNY", 0.04]]');

// (checkCashRegister(19.50, 20.00, [["PENNY", 0.01], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]) === "Insufficient Funds") ? console.log("...OK") : console.log('FAIL: must be "Insufficient Funds"');

// (checkCashRegister(19.50, 20.00, [["PENNY", 0.01], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 1.00], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]) === "Insufficient Funds") ? console.log("...OK") : console.log('FAIL: must be "Insufficient Funds"');

// (checkCashRegister(19.50, 20.00, [["PENNY", 0.50], ["NICKEL", 0], ["DIME", 0], ["QUARTER", 0], ["ONE", 0], ["FIVE", 0], ["TEN", 0], ["TWENTY", 0], ["ONE HUNDRED", 0]]) === "Closed") ? console.log("...OK") : console.log('FAIL: must be "Closed"');