补充

8.10/C - edge.cpp

@@ -0,0 +1,105 @@
+//weiwancheng
+#include<iostream>
+#include<cstdio>
+#include<cmath>
+#include<cstring>
+using namespace std;
+const double inf=1e100,EPS=1e-6;
+const int N=101;
+double l,now;
+int n;
+struct edge
+{
+	double x[2],y[2];
+} e[N];
+//big bug:double->int
+double length(double x1,double y1,double x2,double y2)
+{
+	double x=x1-x2,y=y1-y2;
+	return sqrt(x*x+y*y);
+}
+double cross(double x1,double y1,double x2,double y2)
+{
+	return x1*y2-x2*y1;
+}
+double same(double x0,double y0,double x3,double y3,double x1,double y1,double x2,double y2)
+{
+	double x=x3-x0,y=y3-y0;//y0->x0
+	return cross(x,y,x1-x0,y1-y0)*cross(x,y,x2-x0,y2-y0);
+}
+//WA double 判断正负要用 
+int sign(double d)
+{
+	if(fabs(d)<EPS)
+	{
+		return 0;
+	}
+	else return d>0? 1:-1;
+}
+bool ob(int li,int lj,int ri,int rj)
+{
+	for(int i=li+1; i<ri; i++)
+	{
+		for(int j=0; j<=4; j+=2)
+		{
+//			printf("(%.0lf,%.0lf)(%.0lf,%.0lf)/(%.0lf,%.0lf)(%.0lf,%.0lf):",w[i].x,w[i].y[j],w[i].x,w[i].y[j+1],w[li].x,w[li].y[lj],w[ri].x,w[ri].y[rj]); 
+//			printf("[%.2lf/%.2lf]\n",same(w[i].x,w[i].y[j],w[i].x,w[i].y[j+1],w[li].x,w[li].y[lj],w[ri].x,w[ri].y[rj]),same(w[li].x,w[li].y[lj],w[ri].x,w[ri].y[rj],w[i].x,w[i].y[j],w[i].x,w[i].y[j+1]));
+			//两个都同方向才是，应该&&，错以为|| ,不是0都是真 两个小于0才是香蕉 
+			if(sign(same(w[i].x,w[i].y[j],w[i].x,w[i].y[j+1],w[li].x,w[li].y[lj],w[ri].x,w[ri].y[rj]))<0&&sign(same(w[li].x,w[li].y[lj],w[ri].x,w[ri].y[rj],w[i].x,w[i].y[j],w[i].x,w[i].y[j+1]))<0)
+			{
+				return 0;
+			}
+		}
+	}
+	return 1;
+}
+void find(int ii,int jj)
+{
+	for(int i=0; i<ii; i++)
+	{
+		for(int j=1; j<=4; j++)
+		{
+			l=length(w[ii].x,w[ii].y[jj],w[i].x,w[i].y[j]);
+			now=w[i].val[j]+l;//i j ii,jj搞反了 
+			if(now<w[ii].val[jj]&&ob(i,j,ii,jj))
+			{
+				w[ii].val[jj]=now;
+			}
+//			printf("(%.0lf,%.0lf)(%.0lf,%.0lf):length:%.3lf,now:%.3lf，val:%.3lf\n",w[ii].x,w[ii].y[jj],w[i].x,w[i].y[j],l,now,w[ii].val[jj]); 
+			if(i==0) break;
+		}
+	}
+}
+void doit()
+{
+	for(int i=1; i<=n; i++)
+	{
+		for(int j=1; j<=4; j++)
+		{
+			find(i,j);
+			if(i==n) break;
+		}
+	}
+}
+int main()
+{
+	scanf("%d",&t);
+	while(t--)
+	{
+		scanf("%d",&n);
+		memset(&e,0,sizeof(edge)*(n+1));
+		for(int i=1; i<=n; i++)
+		{
+			for(int j=0; j<2; j++)// 又是j 
+			{
+				scanf("%lf",&e[i].x[j],&e[i].y[j]);
+			}
+		}
+		w[++n].x=10;
+		w[n].y[1]=5;
+		w[n].val[1]=inf;// bug 没赋值 
+		doit();
+		printf("%.2lf\n",w[n].val[1]);
+	}
+
+}

8.10/ce1.cpp

@@ -0,0 +1,31 @@
+10
+1 1 3 3
+0 2 2 0
+
+0 2 2 2
+0 2 2 0
+
+0 2 2 0
+0 2 2 0
+
+0 2 1 1
+0 3 3 0
+
+-1 -1 1 1
+0 0 2 -2
+
+1 1 3 3
+2 1 3 -2
+
+2 2 8 8
+0 2 2 0
+
+2 1 2 3
+0 2 2 0
+
+1 1 2 2
+0 0 2 2
+
+-1 -2 -3 -2
+-99 -99 -3 -3
+

8.10/ce2.cpp

@@ -0,0 +1,19 @@
+6
+1 1 3 3
+0 0 2 3
+
+0 5 7 0
+0 0 1 4
+
+0 2  2 2
+2 3 0 9
+
+2 3 1 4
+0 0 2 2
+
+2 3 2 4
+0 2 2 0
+
+3 2 3 4
+2 2 0 0
+