附WA源码
#include<stdio.h>
#include<math.h>
double d,l,h;
double f(double t){
	double y1,s;
	y1=d*sqrt((t*2/d)*(t*2/d)+1)/2;
	s=2*t/d;//以下防止实数相除失去精度
	if(s>1e-7)return y1+log(sqrt(s*s+1)+s)*d/(2*s)-l;
	else return y1+d/2-l;
}
double bin(double a,double b){//二分法解f(x)=0
	if(fabs(b-a)<1e-4)return (a+b)/2;
	else if(f(a)*f((a+b)/2)<0)return bin(a,(a+b)/2);
	else return bin((a+b)/2,b);
}
main(){
	int t,j;
	double b,ans,i;
	scanf("%d",&t);
	for(j=1;j<=t;j++){
		scanf("%lf%lf%lf%lf",&d,&h,&b,&l);
		if(fabs(b-l)<1){ans=0;goto l1;}
		for(i=1;b/i>d;i++);
		d=b/(i*2);l=l/(i*2);
		ans=bin(0,h);//显然f(0)>0,f(h<0),此区间可以用二分
l1:		printf("case %d:\n",j);
		printf("%.2f\n",h-ans);
		if(j!=t)printf("\n");
	}
}

• 把"case"改成"Case"就过了,整整一天才发现,浪费时间啊 (0) majia001 2006-07-15 11:00:46