谁能给一组强一点的测试数据啊？？？
我下面那个程序考虑了多种特殊情况了！！！还是有错啊。请大牛帮忙看看。

#include <stdio.h>
#include <math.h>
#include <string>
#include <iostream>
using namespace std;
const double pre = 1e-10;
const double Min = -1, Max = 11;


int Comp(double d1, double d2);
struct node{
	double x;
	double y;
	node(double x = 0, double y = 0){
		this->x = x;   //连结构体也有this指针！
		this->y = y;
	}
	bool operator==(node n){
		return Comp(x, n.x) == 0 && Comp(y, n.y) == 0;
	}
	void setNode(double x, double y){
		this->x = x;   //连结构体也有this指针！
		this->y = y;
	}
};

node polygon[100], _polygon[2][100];
int num[2];

double CrossPro(node n1, node n2, node u1, node u2){  //计算叉乘 
	n1.x = n2.x - n1.x;
	n1.y = n2.y - n1.y;
	u1.x = u2.x - u1.x;
	u1.y = u2.y - u1.y;
	return n1.x * u1.y - n1.y * u1.x;
}

int Comp(double d1, double d2){
	double d = d1 - d2;
	if(fabs(d) < pre)
		return 0;
	if(d > 0)
		return 1;
	return -1;
}
bool Cross(node n1, node n2, node u1, node u2){  //判断是否相交
	double d1, d2;
	d1 = CrossPro(n1, u2, n1, n2);
	d2 = CrossPro(n1, n2, n1, u1);
	if(Comp(d1 * d2, 0) < 0)
		return false;
	d1 = CrossPro(u1, n1, u1, u2);
	d2 = CrossPro(u1, u2, u1, n2);
	if(Comp(d1 * d2, 0) < 0)
		return false;
	return true;
}

node CrossDot(node n1, node n2, node u1, node u2){ //求两条线段的交点
	node ans;  
	double s1, s2;
	s1 = fabs(CrossPro(n1, u1, n1, n2));
	s2 = fabs(CrossPro(n1, u2, n1, n2));
	ans.x = (s2 * u1.x + s1 * u2.x) / (s1 + s2);
	ans.y = (s2 * u1.y + s1 * u2.y) / (s1 + s2);
	return ans;

}

double area(node polygon[], int n){  //n为点数
	double ans = 0;
	int i;
	polygon[n] = polygon[0];
	for(i = 0; i < n; i++){
		ans += (polygon[i].x * polygon[i + 1].y - polygon[i].y * polygon[i + 1].x);
	}
	return fabs(ans / 2.0);
}

void Mid(node n1, node n2, node& u1, node& u2){  //该程序尚未验证!
	if(n1.x == n2.x){
		u1.x = Min;
		u2.x = Max;
		u1.y = u2.y = (n1.y + n2.y) / 2.0;
	}else if(n1.y == n2.y){
		u1.y = Min;
		u2.y = Max;
		u1.x = u2.x = (n1.x + n2.x) / 2.0;
	}else{
		u1.x = Min;
		u2.x = Max;
		u1.y = (n1.y + n2.y) / 2.0 - (n2.x - n1.x) * (u1.x - (n1.x + n2.x) / 2.0) / (n2.y - n1.y);
		u2.y = (n1.y + n2.y) / 2.0 - (n2.x - n1.x) * (u2.x - (n1.x + n2.x) / 2.0) / (n2.y - n1.y);
	}
}

void Parallel(node polygon[], int& n, node n1, node n2, node w){ //在检测到线段和多边行的某条边平行之后做处理
	int i;
	int k1, k2;
	if(!(polygon[n - 1] == polygon[0]))
		polygon[n] = polygon[0];
	k1 = CrossPro(n1, w, n1, n2);
	for(i = 0; i < n; i++){
		k2 = CrossPro(n1, polygon[i], n1, n2);
		if(k2 != 0){
			if(Comp(k1 * k2, 0) < 0){ //不在同一侧
				n = 0;
			}
			return;
		}
	}
}

void PrintPoly(node polygon[], int n){
	for(int i = 0; i < n; i++)
		printf("(%lf, %lf)  ", polygon[i].x, polygon[i].y);
	printf("\n\n");
}

void Next(node polygon[], int& n, node n1, node n2, node w){
	if(n == 0)
		return;
	polygon[n] = polygon[0];
	int i, flag, j, a;
	node Cro[2];
	flag = 0;
	int g;
	num[0] = num[1] = 0;
	g = 0;
	/*
	printf("3:\n");
	PrintPoly(polygon, n);
	*/ 
	for(i = 0; i < n; i++){
		_polygon[g][num[g]++] = polygon[i];
		if(Cross(polygon[i], polygon[i + 1], n1, n2)){
			flag = 1;  //表示有交点
			//下一步  还得判断是否平行!!
			//printf("i:%d\n", i);
			a = i - 1;
			if(a < 0)
				a = n - 1;
			if(Comp(CrossPro(polygon[i], polygon[i + 1], n1, n2), 0) == 0){  //如果平行的话
				//printf("parallel\n");
				Parallel(polygon, n, n1, n2, w);
				return ;
			}
			Cro[g] = CrossDot(polygon[i], polygon[i + 1], n1, n2);
			if(!(Cro[g] == polygon[i])){
				_polygon[g][num[g]++] = Cro[g];
			}else{
				a = i - 1;
				if(a < 0)
					a = n - 1; 
				int b1 = CrossPro(n1, polygon[a], n1, n2);
				int b2 = CrossPro(n1, polygon[i + 1], n1, n2);
				int b3 = CrossPro(n1, polygon[i], n1, n2);
				if(Comp(b1 * b2, 0) > 0 || (Comp(b1, 0) == 0 && Comp(b3, 0) == 0 )){
					//printf("w:(%lf, %lf)\n", w.x, w.y);
					Parallel(polygon, n, n1, n2, w);
					return ;
				}

			}
			int gg = (g + 1) % 2;
			_polygon[gg][num[gg]++] = Cro[g];
			if(Cro[g] == polygon[i + 1]){
				a = (i + 2) % n;
				int b1 = CrossPro(n1, polygon[a], n1, n2);
				int b2 = CrossPro(n1, polygon[i + 1], n1, n2);
				int b3 = CrossPro(n1, polygon[i], n1, n2);
				if(Comp(b1 * b3, 0) > 0 || (Comp(b1, 0) == 0 && Comp(b2, 0) == 0 )){
					Parallel(polygon, n, n1, n2, w);
					return ;
				}
				i++;
			}
			g = (g + 1) % 2;

		}
		//printf("i: %d\n", i);
	}
	//判断两个交点是否相等
	if(flag == 0 || Cro[0] == Cro[1]){
		Parallel(polygon, n, n1, n2, w);
		return ;
	}else{
		int k1, k2;
		k1 = CrossPro(n1, w, n1, n2);
		n = 0;
		for(i = 0; i < num[0]; i++){
			k2 = CrossPro(n1, _polygon[0][i], n1, n2);
			if(k2 != 0){
				if(Comp(k1 * k2, 0) > 0){
					//如果在同一侧
					for(i = 0; i < num[0]; i++){
						polygon[i] = _polygon[0][i];
						n = num[0];
					}
					return;
				}
				break;
			}
		}

		for(i = 0; i < num[1]; i++){
			k2 = CrossPro(n1, _polygon[1][i], n1, n2);
			if(k2 != 0){
				if(Comp(k1 * k2, 0) > 0){
					//如果在同一侧
					for(i = 0; i < num[1]; i++){
						polygon[i] = _polygon[1][i];
						n = num[1];
					}
					return;
				}
				break;
			}
		}
	}
	//输出多边形上的点集

}

int main(){
	node n1, n2, u1, u2;
	string str;
	int n = 4;
	double ans = 0;
	polygon[0].setNode(0, 0);
	polygon[1].setNode(10, 0);
	polygon[2].setNode(10, 10);
	polygon[3].setNode(0, 10);
	n1.setNode(0, 0);
	while(scanf("%lf%lf", &n2.x, &n2.y)){
		cin >>str;
		Mid(n1, n2, u1, u2);
		//printf("(%lf, %lf) --> (%lf, %lf)\n", u1.x, u1.y, u2.x, u2.y);
		if(str[0] == 'H'){
			Next(polygon, n, u1, u2, n2);
		}else if(str[0] == 'C'){
			Next(polygon, n, u1, u2, n1);
		}else{
			//判断前后两个点是否相等
			if(!(n1 == n2))
				n = 0;   //如果距离相同，解集就是一条直线，直线是没有面积的
		}
		 /* 
		printf("1:\n");
		PrintPoly(_polygon[0], num[0]);
		printf("2:\n");
		PrintPoly(_polygon[1], num[1]);
		printf("3:\n");
		PrintPoly(polygon, n);
		*/ 
		ans = area(polygon, n);
		printf("%.2lf\n", ans);
		n1 = n2;
		if(fabs(ans) < pre)
			break;
	}
	return 0;
}

/*
测试线段是否相交
1 1
3 3
2 0
1 3


1 1
3 3
1.499 1503
1 3

1 1
3 3
1 1
3 3

面积检验
3 
0 0
2 0
2 2



数据检验

10.0 10.0 Colder
10.0 0.0 Hotter
0.0 0.0 Colder
5.0 5.0  Hotter




*/

• Re:求测试数据！！！ (35) guoxiang 2010-04-10 20:36:44