题解 | #计算商品打折结算金额#

#include <stdio.h>

int main()
{
    double cost = 0;

    while (~scanf("%lf", &cost))
    {
        if (cost >= 100 && cost < 500)
        {
            printf("%.1lf\n", cost * 0.9);
        }
        else if (cost >= 500 && cost < 2000)
        {
            printf("%.1lf\n", cost * 0.8);
        }
        else if (cost >= 2000 && cost < 5000)
        {
            printf("%.1lf\n", cost * 0.7);
        }
        else 
        {
            printf("%.1lf\n", cost * 0.6);
        }
    }

    return 0;
}