这个代码样例全过WA0，求调。

#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
	double l,r,x1,y1,x2,y2,x3,y3;
	scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&l,&r,&x1,&y1,&x2,&y2,&x3,&y3);
	double ans=0x3f3f3f3f3f3f3f3f;
	for(double i=l;i<=r+0.01;i+=0.01){
		double xe=abs(x1-x3)*(1-i)+x1,ye=abs(y1-y3)*(1-i)+y1;
		double xf=abs(x1-x2)*i+x1,yf=abs(y1-y2)*i+y1;
		double xd=abs(x2-x3)*(1-i)+x3,yd=abs(y2-y3)*i+y2;
		//printf("%.12lf %.12lf\n%.12lf %.12lf\n%.12lf %.12lf\n",xe,ye,xf,yf,xd,yd);
		double A=sqrt((xe-xd)*(xe-xd)+(ye-yd)*(ye-yd));
		double B=sqrt((xd-xf)*(xd-xf)+(yd-yf)*(yd-yf));
		double C=sqrt((xf-xe)*(xf-xe)+(yf-ye)*(yf-ye));
		double p=(A+B+C)/2;
		ans=min(ans,sqrt(p*(p-A)*(p-B)*(p-C)));
		//printf("%.2lf %.12lf %.12lf %.12lf %.12lf\n",i,A,B,C,sqrt(p*(p-A)*(p-B)*(p-C)));
	}
	printf("%.12lf",ans);
	return 0;
}
#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
	double l,r,x1,y1,x2,y2,x3,y3;
	scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&l,&r,&x1,&y1,&x2,&y2,&x3,&y3);
	double ans=0x3f3f3f3f3f3f3f3f;
	for(double i=l;i<=r+0.01;i+=0.01){
		double xe=abs(x1-x3)*(1-i)+x1,ye=abs(y1-y3)*(1-i)+y1;
		double xf=abs(x1-x2)*i+x1,yf=abs(y1-y2)*i+y1;
		double xd=abs(x2-x3)*(1-i)+x3,yd=abs(y2-y3)*i+y2;
		//printf("%.12lf %.12lf\n%.12lf %.12lf\n%.12lf %.12lf\n",xe,ye,xf,yf,xd,yd);
		double A=sqrt((xe-xd)*(xe-xd)+(ye-yd)*(ye-yd));
		double B=sqrt((xd-xf)*(xd-xf)+(yd-yf)*(yd-yf));
		double C=sqrt((xf-xe)*(xf-xe)+(yf-ye)*(yf-ye));
		double p=(A+B+C)/2;
		ans=min(ans,sqrt(p*(p-A)*(p-B)*(p-C)));
		//printf("%.2lf %.12lf %.12lf %.12lf %.12lf\n",i,A,B,C,sqrt(p*(p-A)*(p-B)*(p-C)));
	}
	printf("%.12lf",ans);
	return 0;
}

这个代码样例没过WA20？

#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
	double l,r,x1,y1,x2,y2,x3,y3;
	scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&l,&r,&x1,&y1,&x2,&y2,&x3,&y3);
	double a=sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
	double b=sqrt((x2-x3)*(x2-x3)+(y2-y3)*(y2-y3));
	double c=sqrt((x3-x1)*(x3-x1)+(y3-y1)*(y3-y1));
	double ans=0x3f3f3f3f;
	for(double i=l;i<=r+0.01;i+=0.01){
		double A=a*i;
		double B=b*i;
		double C=c*i;
		A=max(a-A,A);
		B=max(b-B,B);
		C=max(c-C,C);
		double p=(A+B+C)/2;
		ans=min(ans,sqrt(p*(p-A)*(p-B)*(p-C)));
		//printf("%.2lf %.12lf %.12lf %.12lf %.12lf\n",i,A,B,C,sqrt(p*(p-A)*(p-B)*(p-C)));
	}
	printf("%.12lf",ans);
	return 0;
}