Breaking Down my money - c

Question

Can anybody help me with my code? my program shows wrong output, when i try to enter the number 2880 it shows 'Invalid Input'. the number 2880 is divisible by 20 right ? why does it go Invalid
int money, x[6],y[6],total;
x[0] = 1000; x[1] = 500; x[2] = 200; x[3] = 100; x[4] = 50; x[5] = 20;
system("cls");
printf("Enter your Money: ");
scanf("%d", &money);
total = money;
printf("\nBreakdown:\n");
for(int i=0;i < 6; i++){
y[i] = ( money - (money % x[i]) )/x[i];
money = (money % x[i]);
if (y[i] != 0)
printf("%10d x %d = %5d \n",x[i], y[i], (x[i] * y[i]));
}
printf("---------------------------\n");
printf("Total: %d",total);
if(money>0){
system("cls");
printf("Invalid Input !");
}
getch();
i am expecting my output will be like this:
Enter your Money: 2880
Breakdown:
1000 x 2 = 2000
500 x 1 = 500
200 x 1 = 200
100 x 1 = 100
20 x 4 = 80
---------------------------
Total: 2880

Answer 1

You could add an if clause in your for loop to ignore division by 50$ if the money is a multiple of 20, if that is what you actually want.
Otherwise, your program is doing exactly what you want it to do.
int money () {
int money, total;
int x[6] = { 1000, 500, 200, 100, 50, 20 };
int y[6] = { 0, 0, 0, 0, 0, 0 };
printf("Enter your money: ");
scanf("%d", &money);
total = money;
printf("\nBreakdown:\n");
for(int i=0; i<6; i++) {
if (x[i] == 50 && money % 20 == 0) {
continue;
}
y[i] = (money - (money % x[i]))/x[i];
money = (money % x[i]);
}
if (money > 0 && y[3] > 0) {
money += 50;
if (money % 20 == 0) {
y[5] = money / 20;
y[3] = y[3] - 1;
y[4] = y[4] + 1;
money = 0;
}
}
for(int i=0; i<6; i++) {
if (y[i] != 0) {
printf("\t %4d x%5d = %5d \n", x[i], y[i], (x[i] * y[i]));
}
}
printf("\t---------------------------\n");
printf("\t Total: %5d\n\n", total);
if(money > 0) {
printf("Invalid input!");
}
}
EDIT: I have added an if clause for sums like $2810 that has a remainder of 10$ (if decomposed in the standard manner) and can hence be differently decomposed. The idea is to check if by adding 50$, the remainder can be nicely divided into a number of 20$. This 50$ comes from breaking down an existing 100$.
E.g.
$210 is first decomposed into: $100 x 2, and a remainder of $10, hence INVALID
So, instead, we change a $100 into 2 x $50 such that we get
$100 x 1, $50 x 1, and a remainder of $10
We sum the $50 with the remaining $10 to get $60, which is broken down into $20 x 3
Therefore, we get $210 = 1 x $100, 1 x $50, 3 x $20.

Answer 2

Well, when I compiled this program, it worked successfully, just that the after showing the breakdown, it showed invalid input. I think you want to print invalid input when the money inputted is less than 0, as printing invalid input when money is more than 0 does not make sense. I think you should just change
if(money>0){
to
if(money<0){
Also, your breakdown is wrong, as it leaves 10 behind, and the sum just adds upto 2870 instead of 2880.
EDIT: You just now mentioned in your comment that you print invalid input when there is a remainder. Next time please mention that in the question, as in confuses the answerers of the question, just like I got confused. I'll get back with a solution, but I won't delete my original answer.