#include<iostream>
#include<cstdio>
#include<vector>
#include<string>
#include<cstring>
#include<algorithm>
#define _USE_MATH_DEFINES
#include<cmath>
using namespace std;


#define INF 1e+10
#define EPS 1e-10
#define EQ(a,b) (abs(a-b)<EPS)

//誤差を考慮して足し算
double add(double a,double b){
	if(abs(a+b) < EPS*(abs(a)+abs(b)))return 0;
	return a+b;
}
struct P{//2次元ベクトル
	double x,y;
	P(){}
	P(double x,double y):x(x),y(y){}
	P operator + (P p){
		return P(add(x,p.x),add(y,p.y));
	}
	P operator - (P p){
		return P(add(x,-p.x),add(y,-p.y));
	}
	P operator * (double d){
		return P(x*d,y*d);
	}
	P operator / (double d){
		return P(x/d,y/d);
	}
	double dot(P p){//内積
		return add(x*p.x,y*p.y);
	}
	double det(P p){//外積
		return add(x*p.y,-y*p.x);
	}
	bool equal(P p){
		return (x-p.x)*(x-p.x)+(y-p.y)*(y-p.y) < EPS*EPS;
	}
};
//typedef pair<P,P> Line;

//線分p1-p2上に点qがあるか判定
bool on_seg(P p1,P p2,P q){
	return (p1-q).det(p2-q)==0 && (p1-q).dot(p2-q)<=0;
}
//直線p1-p2と直線q1-q2の交点
P intersection(P p1,P p2,P q1,P q2){
	return p1+(p2-p1)*( (q2-q1).det(q1-p1)/(q2-q1).det(p2-p1) );
}


//線分p1-p2と線分q1-q2が交差するか
bool intersecting(P p1,P p2,P q1,P q2){
	if(on_seg(p1,p2,q1)||on_seg(p1,p2,q2)||on_seg(q1,q2,p1)||on_seg(q1,q2,p2))return true;
	if((p1-p2).det(q1-q2)==0 )return false;//平行
	P a=intersection(p1,p2,q1,q2);
	return on_seg(p1,p2,a) && on_seg(q1,q2,a);
}
//原点中心回転
P rotate(P p,double rad){
	double s=sin(rad),c=cos(rad);
	return P(c*p.x-s*p.y, s*p.x+c*p.y);
}
//originを中心に回転
P rotate(P p,double rad,P origin){
	return origin + rotate(p - origin,rad);
}
//二点間の距離
double dist(P p,P q){
	p = p-q;
	return sqrt(p.x*p.x+p.y*p.y);
}
//単位ベクトルに変換
P to_unit(P p){
	double d = sqrt(p.x*p.x+p.y*p.y);
	return p/d;
}
//円同士の交点を計算
pair<P,P> circle_intersection(double x1,double y1,double r1,double x2,double y2,double r2){
	double rad = atan2(y2-y1,x2-x1);
	x2 -= x1;
	y2 -= y1;
	P tmp = rotate(P(x2,y2),-rad);
	x2 = tmp.x;
	y2 = tmp.y;
	double x = (r1*r1-r2*r2+x2*x2)/(2*x2);
	if(abs(r1) < abs(x))return make_pair(P(0,0),P(0,0));//交点なし
	double y = sqrt(r1*r1-x*x);
	return make_pair( P(x1,y1)+rotate(P(x,y),rad) ,  P(x1,y1)+rotate(P(x,-y),rad) );
}
//2点を通る円の中心座標
pair<P,P> circle_on_2P(P p,P q,double r){
	if(2*r < dist(p,q))return make_pair(P(0,0),P(0,0));//解なし
	if(q.x < p.x)swap(p,q);
	q = q - p;
	double rad = atan2(q.y,q.x);
	P tmp = rotate(q,-rad);
	double x = tmp.x/2;
	double y = sqrt(4*r*r-tmp.x*tmp.x)/2;
	return make_pair( p+rotate(P(x,y),rad) ,  p+rotate(P(x,-y),rad) );
}
//線分と点の距離
double dist_LP(P p1,P p2,P q){
	double dx,dy;
	dx = p1.x-p2.x;
	dy = p1.y-p2.y;
	double d = min(dist(p1,q) ,dist(p2,q));
	pair<P,P> normal = make_pair(q+to_unit(P(-dy,dx))*d ,q+to_unit(P(dy,-dx))*d);//法線ベクトル
	if(intersecting(p1,p2,normal.first,normal.second)){
		return dist(q, intersection(p1,p2,normal.first,normal.second));
	}
	return d;
}
//線分間の距離
double dist_LL(P p1,P p2,P q1,P q2){
	if(intersecting(p1,p2,q1,q2))return 0;
	return min( min(dist_LP(p1,p2,q1),dist_LP(p1,p2,q2))
		,min(dist_LP(q1,q2,p1),dist_LP(q1,q2,p2)) );
}
//ラジアンに変換
double radian(double angle){
	return angle/180.0*M_PI;
}



int minx[50],miny[50],maxx[50],maxy[50],h[50];
int n;
int sx,sy,ex,ey;

bool in_block(int x,int y,int minx,int miny,int maxx,int maxy){
	return minx<=x&&x<=maxx&&miny<=y&&y<=maxy;
}
bool on_line(){//ライン上にブロックがある
	P s(sx,sy),e(ex,ey);
	for(int i=0;i<n;i++){
		P a(minx[i],miny[i]),b(minx[i],maxy[i]),c(maxx[i],miny[i]),d(maxx[i],maxy[i]);
		if(intersecting(s,e,a,b))return true;
		if(intersecting(s,e,a,c))return true;
		if(intersecting(s,e,b,d))return true;
		if(intersecting(s,e,c,d))return true;
		if(in_block(sx,sy,minx[i],miny[i],maxx[i],maxy[i]))return true;
		if(in_block(ex,ey,minx[i],miny[i],maxx[i],maxy[i]))return true;
	}
	return false;
}
double square(double a){
	return a*a;
}
double min(double a,double b){
	return a<b?a:b;
}
bool f(double r){
	P s(sx,sy),e(ex,ey);
	for(int i=0;i<n;i++){
		P a(minx[i],miny[i]),b(minx[i],maxy[i]),c(maxx[i],miny[i]),d(maxx[i],maxy[i]);
		double hei = min(r,h[i]);
		double mind=INF;
		mind = min(mind,dist_LL(s,e,a,b));
		mind = min(mind,dist_LL(s,e,a,c));
		mind = min(mind,dist_LL(s,e,b,d));
		mind = min(mind,dist_LL(s,e,c,d));
		double di = sqrt(square(mind)+square(r-hei));
		if(di<r)return false;
	}
	return true;
}
int main(){
	while(cin>>n,n){
		cin>>sx>>sy>>ex>>ey;
		for(int i=0;i<n;i++){
			cin>>minx[i]>>miny[i]>>maxx[i]>>maxy[i]>>h[i];
		}
		if(on_line()){
			printf("%.4f\n",0.0);
		}else{
			double lb=0,ub=1001;
			for(int i=0;i<25;i++){
				double m=(lb+ub)/2;
				if(f(m))lb=m;
				else ub=m;
			}
			printf("%.4f\n",lb);
		}
	}
	return 0;
}

Measured memory_bytes: 1200