题解 | #网购#

int main() {
    float c; //衣服
    int month, day;
    int flag;
    float money;
    scanf("%f %d %d %d", &c, &month, &day, &flag);
    if (month == 11 && day == 11) {     //双11七折
        money = c * 0.7;
        if (flag == 1) {             
            money = money - 50;
            if (money <= 0) {           //如果小于0 商家不会做亏本生意
                float money = 0;
                printf("%.2f", money);  //输出0
            } else {
                printf("%.2f", money);  //如果不小于0输出折扣后减去优惠券的
            }
        }
     else  //与第一个if配对
        {
            printf("%.2f",money);    //不在双11原价
        }
    }
    //---------------------------------------------------------------------------
       if (month == 12 && day == 12) {     //双12八折
        money = c * 0.8;
        if (flag == 1) {             
            money = money - 50;
            if (money <= 0) {           //如果小于0 商家不会做亏本生意
                float money = 0;
                printf("%.2f", money);  //输出0
            } else {
                printf("%.2f", money);  //如果不小于0输出折扣后减去优惠券的
            }
        }
     else 
        {
            printf("%.2f",money);    //不在双12原价
        }
    }
}