For one of my classes, we had to find a way to make a certain amount of change given an arbitrary amount of coins, with the least amount of coins. Here is my code below:
public class Changemaker {
public static void main ( String[] args ) {
int amount = Integer.parseInt(args[args.length-1]);
int coins = args.length - 1;
if (amount < 0){
throw new IllegalArgumentException("IMPROPER AMOUNT");
} else {
for (int i = 1; i <= coins; i++) {
int coin = Integer.parseInt(args[i]);
if (coin <= 0){
throw new IllegalArgumentException("IMPROPER DENOMINATION");
} else {
for (int j = 1; j <= coins; j++) {
int validCoin = Integer.parseInt(args[j]);
if (validCoin == coin && j != i ) {
throw new IllegalArgumentException("DUPLICATE DENOMINATION");
}
}
}
try {
String firstCoin = args[1];
} catch (ArrayIndexOutOfBoundsException e) {
System.out.println("INSUFFICIENT DATA");
throw new ArrayIndexOutOfBoundsException(" ");
}
}
}
Tuple [][] table = new Tuple [coins][amount + 1];
for(int x = 0; x < coins; x++) {
for (int i = 0; i <= amount; i++) {
Tuple tuple = new Tuple (coins);
table[x][i] = tuple;
}
}
for (int i = 1; i <= amount; i++) {
Tuple tuple = table[0][i];
int coin = Integer.parseInt(args[1]);
int total = i;
int remainder = total % coin;
int coinAmt= (int)Math.floor(total / coin);
if (remainder == 0) {
tuple.setElement(0, coinAmt);
}
}
for(int x = 1; x < coins; x++) {
int coin = Integer.parseInt(args[x + 1]);
for (int i = 1; i <= amount; i++) {
Tuple tuple = table[x][i];
int total = i;
int remainder = total % coin;
int coinAmt= (int)Math.floor(total / coin);
if (remainder == 0) {
tuple.setElement(x, coinAmt);
int optimalRow = optimalCheck(table, tuple, x, i);
Tuple optimalTuple = table[optimalRow][i];
tuple.copy(optimalTuple);
} else if (remainder != 0 && amount < coin) {
tuple.copy(table[x - 1][i]);
} else if (remainder != 0 && amount > coin) {
tuple.setElement(x, coinAmt);
Tuple remainderTuple = table[x][remainder];
tuple.add(remainderTuple);
int optimalRow = optimalCheck(table, tuple, x, i);
Tuple optimalTuple = table[optimalRow][i];
tuple.copy(optimalTuple);
}
}
}
Tuple finalAnswer = table[coins - 1][amount];
String result = "";
result = result + finalAnswer.total() + " COIN(S) IN TOTAL: ";
for (int i = 0; i < coins; i++) {
result = result + finalAnswer.getElement(i) + " x " + args[i + 1] + " cent , ";
}
if (finalAnswer.total() == 0) {
System.out.println("AMOUNT CANNOT BE MADE");
} else {
System.out.println(result);
}
}
public static int optimalCheck(Tuple[][] table, Tuple tuple, int row, int column) {
int total = tuple.total();
int optimalRow = 0;
for (int i = 0; i <= row; i++ ){
int checkedTotal = table[i][column].total();
if (checkedTotal < total && checkedTotal > 0) {
optimalRow = optimalRow + i;
break;
} else if (checkedTotal == total && i == row) {
optimalRow = optimalRow + row;
break;
}
}
return optimalRow;
} }
For the most part, my code is correct. The only thing wrong with it is that it counts the amount of change to make as a denomination, and it cuts out my first denomination amount.
So, for example, if I put 1 5 10 25 133 in the command line (1,5,10, and 25 cent coins to make 133 cents), it returns:
1 COIN(S) IN TOTAL: 0 x 5 cent , 0 x 10 cent , 0 x 25 cent , 1 x 133 cent ,
I looked at the code, and I don't see where I went wrong. Can anyone tell me where I made the error? Thanks a ton.
