C语言经典例题-求最少数量钞票

编写一个程序，要求用户输入一个美金数量，然后显示出如何用最少的20美元、10美元、5美元和1美元来付款:
 

# include <stdio.h>

int main()
{
	int amount;
	int twentyDollars = 0;//定义20美元钞票数量
	int tenDollars = 0;
	int fiveDollars = 0;
	int oneDollars = 0;

	printf("Enter an dollar amount: ");
	scanf("%d", &amount);

	twentyDollars = amount / 20;
	tenDollars = (amount - twentyDollars *20) / 10;//计算10美元钞票数量
	fiveDollars = (amount - twentyDollars *20 - tenDollars *10) / 5;
	oneDollars = amount - twentyDollars *20 - tenDollars *10- fiveDollars;

	printf("$20 bills: %d\n", twentyDollars);
	printf("$10 bills: %d\n", tenDollars);
	printf("$5 bills: %d\n", fiveDollars);
	printf("$1 bills: %d\n", oneDollars);

	return 0;
}