题解 | #Grading#

#include <iostream>
using namespace std;

int main() {
    double p,t,g1,g2,g3,gl;
    while(cin>>p>>t>>g1>>g2>>g3>>gl){
        double res=0;
        if(abs(g1-g2)<=t){
            printf("%.1lf",(g1+g2)/2);
        }else{
            int l1=g1-t,r1=g1+t;
            int l2=g2-t,r2=g2+t;
            if((g3>=l1&&g3<=r1)&&(g3<l2||g3>r2)){
                printf("%.1lf",(g1+g3)/2);
            }else if((g3>=l2&&g3<=r2)&&(g3<l1||g3>r1)){
                printf("%.1lf",(g2+g3)/2);
            }else if(g3>=l1&&g3<=r1&&g3>=l2&&g3<=r2){
                printf("%.1lf",max(max(g1,g2),g3));
            }else{
                printf("%.1lf",gl);
            }
        }
    }
    return 0;
}