C++14(g++5.4) 解法, 执行用时: 6ms, 内存消耗: 504K, 提交时间: 2020-02-16 22:15:42

#include<bits/stdc++.h>
using namespace std;
double ax,ay,bx,by,cx,cy,dx,dy,p,q,r;
double dist(double x1,double y1,double x2,double y2){
	return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
} 
double check(double x,double y){
	double xl=cx,xr=dx,yl=cy,yr=dy;
	while(fabs(xr-xl)>1e-6||fabs(yr-yl)>1e-6){
		double x1,x2,y1,y2;
		x1=xl+(xr-xl)/3.0;
		x2=xr-(xr-xl)/3.0;
		y1=yl+(yr-yl)/3.0;
		y2=yr-(yr-yl)/3.0;
		double t1=dist(1.0*ax,1.0*ay,x,y)/p+dist(x,y,x1,y1)/r+dist(x1,y1,1.0*dx,1.0*dy)/q;
		double t2=dist(1.0*ax,1.0*ay,x,y)/p+dist(x,y,x2,y2)/r+dist(x2,y2,1.0*dx,1.0*dy)/q;
		if(t1<=t2){xr=x2;yr=y2;}
		else xl=x1,yl=y1;
	}
	return dist(1.0*ax,1.0*ay,x,y)/p+dist(x,y,xl,yl)/r+dist(xl,yl,1.0*dx,1.0*dy)/q;
}
int main(){
	cin>>ax>>ay>>bx>>by;
	cin>>cx>>cy>>dx>>dy;
	cin>>p>>q>>r;
	double xl,xr,yl,yr;
	xl=ax,xr=bx,yl=ay,yr=by;
	while(fabs(xr-xl)>1e-6||fabs(yr-yl)>1e-6){
		double x1,x2,y1,y2;
		x1=xl+(xr-xl)/3.0;
		x2=xr-(xr-xl)/3.0;
		y1=yl+(yr-yl)/3.0;
		y2=yr-(yr-yl)/3.0;
		if(check(x1,y1)<check(x2,y2))
			xr=x2,yr=y2;
		else xl=x1,yl=y1;
	}
	printf("%.2lf\n",check(xl,yl));
	return 0;
}

C++(g++ 7.5.0) 解法, 执行用时: 3ms, 内存消耗: 408K, 提交时间: 2023-03-06 18:07:00

#include<bits/stdc++.h>
using namespace std;
double Ax,Ay,Bx,By,Cx,Cy,Dx,Dy,p,q,r,ans;
double check(double x,double y)
{
	double P1x=Ax+(Bx-Ax)*x,P1y=Ay+(By-Ay)*x,P2x=Cx+(Dx-Cx)*y,P2y=Cy+(Dy-Cy)*y;
	return sqrt((P1x-Ax)*(P1x-Ax)+(P1y-Ay)*(P1y-Ay))/p+sqrt((Dx-P2x)*(Dx-P2x)+(Dy-P2y)*(Dy-P2y))/q+sqrt((P2x-P1x)*(P2x-P1x)+(P2y-P1y)*(P2y-P1y))/r;
}
double find2(double x,double l,double r)
{
	double res=0.0;
	while(r-l>=1e-6)
	{
       double midl=l+(r-l)/3;
	   double midr=r-(r-l)/3;
	   double res1=check(x,midl);
	   double res2=check(x,midr);
	   if(res1<res2)
	    {
		 r=midr;
		 res=res1;
	   }
	   else l=midl,res=res2;
	}
	return res;
}
void find1(double l,double r)
{
	while(r-l>=1e-6)
	{
	   double midl=l+(r-l)/3;
	   double midr=r-(r-l)/3;
	   double res1=find2(midl,0,1);
	   double res2=find2(midr,0,1);
	   if(res1<res2)
	   {
		  r=midr;
		  ans=res1;
	   }
	   else
	   {
	   	   l=midl;
           ans=res2;
	   }

	}
}
int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>Ax>>Ay>>Bx>>By>>Cx>>Cy>>Dx>>Dy>>p>>q>>r;
	find1(0,1);
	printf("%.2f",ans);
}

C++(clang++ 11.0.1) 解法, 执行用时: 513ms, 内存消耗: 700K, 提交时间: 2023-07-18 20:00:24

#include<bits/stdc++.h>
using namespace std;
#define int long long

double getDis(double x1,double y1,double x2,double y2)
{
	return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
void __main__()
{
	double ax,ay,bx,by,cx,cy,dx,dy;cin>>ax>>ay>>bx>>by>>cx>>cy>>dx>>dy;
	double p,q,r;cin>>p>>q>>r;
	int tim=5000;
	double res=getDis(ax,ay,dx,dy)/r,ix=ax,iy=ay;
	for(int i=0;i<=tim;++i)
	{
		ix=ax+(bx-ax)*i/tim,iy=ay+(by-ay)*i/tim;
		double jx=cx,jy=cy;
		for(int j=0;j<=tim;++j)
			jx=cx+(dx-cx)*j/tim,jy=cy+(dy-cy)*j/tim,
			res=min(res,getDis(ax,ay,ix,iy)/p+getDis(ix,iy,jx,jy)/r+getDis(jx,jy,dx,dy)/q);
	}
	cout<<res<<endl;
}

signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	cout<<fixed<<setprecision(2);
	__main__();
	system("pause");
	return 0;
}