FCC算法题--Exact Change

题目：

设计一个收银程序 checkCashRegister() ，其把购买价格(price)做为第一个参数 , 付款金额 (cash)做为第二个参数, 和收银机中零钱 (cid) 做为第三个参数.

cid 是一个二维数组，存着当前可用的找零.

当收银机中的钱不够找零时返回字符串 "Insufficient Funds". 若是正好则返回字符串 "Closed".

不然, 返回应找回的零钱列表,且由大到小存在二维数组中.

当你遇到困难的时候，记得查看错误提示、阅读文档、搜索、提问。

这是一些对你有帮助的资源:

• Global Object

 

  1 function checkCashRegister(price, cash, cid) {
  2   var change; 
  3   var sumCid = 0;
  4   
  5 // Here is your change, ma'am.
  6 
  7   //找零(change)，付款(cash)，购买价格(price)，收银机中零钱(cid)
  8   change = cash - price;
  9   
 10   //计算零钱总额
 11   for (var i = 0; i < cid.length; i++) {
 12     sumCid += cid[i][1];
 13   } 
 14   sumCid = Number(sumCid.toFixed(2));  //保留两位小数
 15 
 16   if (sumCid < change) {
 17     return "Insufficient Funds";  //余额不足
 18   } else if (sumCid === change) {
 19     return "Closed";
 20   } else {
 21       // 1.零钱不够,返回余额不足
 22       // 2.零钱足够,找回零钱
 23       return overChange(change, cid, sumCid);
 24   } 
 25 }
 26 
 27 function overChange(change, arr, sumCid) {
 28   var array = [];
 29   var len = arr.length;
 30   
 31   for (var i = len - 1; i >= 0; i--) {
 32       if (arr[i][1] === 0) continue;
 33 
 34       if (arr[i][1] < change) {
 35         array.push(arr[i]);
 36       change -= arr[i][1];
 37       change = Number(change.toFixed(2));
 38       }
 39 
 40       else if (arr[i][1] > change) {
 41       var x = arr[i][0];  // 取得零钱名称
 42         var y = 0;
 43 
 44         switch(x) {
 45           case "ONE HUNDRED":
 46             y = Math.floor(change / 100) * 100;
 47             break;
 48           case "TWENTY":
 49             y = Math.floor(change / 20) * 20;
 50             break;
 51           case "TEN":
 52             y = Math.floor(change / 10) * 10;
 53             break;
 54           case "FIVE":
 55               y = Math.floor(change / 5) * 5;
 56               break;
 57             case "ONE":
 58               y = Math.floor(change / 1);
 59               break;
 60             case "QUARTER":
 61               y = Math.floor(change / 0.25) * 0.25;
 62               break;
 63             case "DIME":
 64               y = Math.floor(change / 0.10) * 0.10;
 65               break;
 66             case "NICKEL":
 67               y = Math.floor(change / 0.05) * 0.05;
 68               break;
 69             case "PENNY":
 70               y = Math.floor(change / 0.01) * 0.01;
 71               break;
 72        }
 73 
 74         if (y === 0 && sumCid - arr[i][1] < change) {
 75         return "Insufficient Funds";              
 76         }
 77 
 78         else if (y === 0) {
 79           continue;
 80         }
 81 
 82         else {
 83             if (y < 1) {
 84               y = y;
 85             }           
 86         var array1 = [];
 87           array1.push(arr[i][0]);
 88           array1.push(y);
 89           array.push(array1);
 90         change -= y;
 91         change = Number(change.toFixed(2));
 92       }
 93       }
 94   }
 95 
 96   if (change === 0) {
 97       return array;
 98   } else {
 99       return "Insufficient Funds";
100   }
101   
102 }
103 
104 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]]);

 

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]]) 应该返回一个数组.

 

 

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]]) 应该返回一个字符串.

 

 

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]]) 应该返回一个字符串.

 

 

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]]) 应该返回  [["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]]) 应该返回  [["TWENTY", 60.00], ["TEN", 20.00], ["FIVE", 15], ["ONE", 1], ["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]]) 应该返回 "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]]) 应该返回 "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]]) 应该返回 "Closed".

 

---------------------------------------------------------------------------------------

 

个人 Free Code Camp地址