> #include <stdio.h>
> #include <math.h>
> #include <float.h>
> 
> const double sec = 4.8481368110953599358991410235795e-6;
> const double radius = 6875.0 / 2;
> 
> int main(void)
> {
> 	char line[80];
> 	double lat, lng, th, dist;
> 	double x1, y1, z1;
> 	double x2, y2, z2;
> 	int d, m, s;
> 	char c;
> 	_controlfp(PC_64, MCW_PC);
> 	while(scanf("%s", line), line[0] == 'M')
> 	{
> 		gets(line);
> 		gets(line);
> 		gets(line); //弄掉前三行
> 		scanf("%d^%d'%d\" %c", &d, &m, &s, &c);
> 		s += m * 60 + d * 3600;
> 		lat = s * sec;
> 		if(c == 'S')
> 		{
> 			lat = -lat;
> 		}
> 		gets(line);
> 		scanf("and %d^%d'%d\" %c", &d, &m, &s, &c);
> 		s += m * 60 + d * 3600;
> 		lng = s * sec;
> 		if(c == 'W')
> 		{
> 			lng = -lng;
> 		}
> 		x1 = cos(lat) * cos(lng);
> 		y1 = cos(lat) * sin(lng);
> 		z1 = sin(lat);//球坐标到直角坐标
> 		gets(line);
> 		gets(line);
> 		scanf("%d^%d'%d\" %c", &d, &m, &s, &c);
> 		s += m * 60 + d * 3600;
> 		lat = s * sec;
> 		if(c == 'S')
> 		{
> 			lat = -lat;
> 		}
> 		gets(line);
> 		scanf("and %d^%d'%d\" %c", &d, &m, &s, &c);
> 		s += m * 60 + d * 3600;
> 		lng = s * sec;
> 		if(c == 'W')
> 		{
> 			lng = -lng;
> 		}
> 		x2 = cos(lat) * cos(lng);
> 		y2 = cos(lat) * sin(lng);
> 		z2 = sin(lat);
> 		th = acos(x1 * x2 + y1 * y2 + z1 * z2);//求夹角
> 		dist = th * radius;
> 		dist = 0.01 * floor(dist * 100.0);//correct to是截尾吧？
> 		gets(line);
> 		gets(line);
> 		printf("The distance to the iceberg: %.2lf miles.\n", dist);
> 		if(dist < 100.0)
> 		{
> 			puts("DANGER!");
> 		}
> 	}
> 	return 0;
> }

• 是啊，保证输出的答案和你比较的结果是一致的 (0) hawk 2005-03-30 10:38:06