题解 | #网购#

注意，浮点数最好与浮点数进行运算

#include <stdio.h>

int main() {
    double val;
    int month,day,youhui;

    scanf("%lf%d%d%d%d",&val,&month,&day,&youhui);
    
    if(month==11&&day==11)
    {
        val*=0.7;
        if(youhui==1)
        {
            val-=50.0;
        }
    }else if(month==12&&day==12)
    {
        val*=0.8;
        if(youhui==1)
        {
            val-=50.0;
        }
    }
    if(val<=0)
    {
        val=0.0;
    }
    printf("%.2lf",val);
    return 0;
}