#include <bits/stdc++.h>
                            #include<iostream>
                            #include<cstdio>
                            #include<vector>
                            #include<queue>
                            #include<map>
                            #include<cstring>
                            #include<string>
                            #include <math.h>
                            #include<algorithm>
                        //    #include <boost/multiprecision/cpp_int.hpp>
                            #include<functional>
                     #define int long long
                            #define inf  1000000007
                            #define pa pair<int,int>
                            #define ll long long
                            #define pal pair<double,pa>
                            #define ppa pair<pa,int>
                            #define ppap pair<int,pa>
                            #define ssa pair<string,int>
                            #define  mp make_pair
                            #define  pb push_back
                            #define EPS (1e-10)
                            #define equals(a,b) (fabs((a)-(b))<EPS)
                     
                            using namespace std;
                  
                            class Point{
                            	public:
                            	double x,y;
                            	Point(double x=0,double y=0):x(x),y(y) {}
                            	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                            	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                            	Point operator * (double a) {return Point(x*a,y*a);}
                            	Point operator / (double a) {return Point(x/a,y/a);}
                            	double absv() {return sqrt(norm());}
                            	double norm() {return x*x+y*y;}
                            	bool operator < (const Point &p) const{
                            		return x != p.x ? x<p.x: y<p.y;
                            	}
                            	bool operator == (const Point &p) const{
                            		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                            	}
                            };
                            typedef Point Vector;
                     
                            struct Segment{
                            Point p1,p2;
                            };
                             double dot(Vector a,Vector b){
                            	return a.x*b.x+a.y*b.y;
                            }
                            double cross(Vector a,Vector b){
                            	return a.x*b.y-a.y*b.x;
                            }
                        
bool parareru(Point a,Point b,Point c,Point d){
//	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
	return abs(cross(a-b,d-c))<EPS;
}
double distance_ls_p(Point a, Point b, Point c) {
  if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
  if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
  return abs(cross(b-a, c-a)) / (b-a).absv();
}
bool is_intersected_ls(Segment a,Segment b) {
	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){
//		cout<<"sss"<<endl;
		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
		return false;
	}
  else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
}

double segment_dis(Segment a,Segment b){
	if(is_intersected_ls(a,b))return 0;
	double r=distance_ls_p(a.p1, a.p2, b.p1);
	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
	return r;
}


                string itos( int i ) {
                ostringstream s ;
                s << i ;
                return s.str() ;
                }
                 
                int gcd(int v,int b){
                	if(v>b) return gcd(b,v);
                	if(v==b) return b;
                	if(b%v==0) return v;
                	return gcd(v,b%v);
                }
 
                double distans(double x1,double y1,double x2,double y2){
                	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                	return sqrt(rr);
                	
                }
                /*}
int pr[100010];
//int inv[100010];
 
int beki(int wa,int rr){
	if(rr==0) return 1ll;
	if(rr==1) return wa;
	if(rr%2==1) return (beki(wa,rr-1)*wa)%inf;
	int zx=beki(wa,rr/2);
	return (zx*zx)%inf;
}
  
void gya(){
	pr[0]=1;
	for(int i=1;i<100010;i++){
		pr[i]=(pr[i-1]*i)%inf;
	}
	for(int i=0;i<100010;i++) inv[i]=beki(pr[i],inf-2);
	
}

*/

                         //----------------kokomade tenpure------------


Segment p[210],path;
Point pp[210];
int n;
double h[210];
bool ch(double r){
	
	for(int i=0;i<4*n;i++){
		double t=segment_dis(p[i],path);
		if(t>=r) continue;
		if(r-sqrt(r*r-t*t)<=h[i/4])return false;
	}
	return true;
	
}


signed main(){

	int cnt=0;
	while(1){
		
		cin>>n;
		if(n==0) return 0;
//cout<<cnt<<" "<<n<<endl;
		
		cnt++;
		cin>>path.p1.x>>path.p1.y>>path.p2.x>>path.p2.y;
		bool b=false;
		for(int i=0;i<n;i++){
			double ax,ay,bx,by;
			cin>>ax>>ay>>bx>>by;
			if(ax <= path.p1.x &&path.p1.x<=bx &&ay <= path.p1.y &&path.p1.y<=by){
				if(ax <= path.p2.x &&path.p2.x<=bx &&ay <= path.p2.y &&path.p2.y<=by){
					b=1;
				}
			}
			
			pp[i*4].x=ax;
			pp[i*4].y=ay;
			pp[1+i*4].x=ax;
			pp[1+i*4].y=by;
			pp[2+i*4].x=bx;
			pp[2+i*4].y=by;
			pp[3+i*4].x=bx;
			pp[3+i*4].y=ay;
			
			p[i*4].p1=pp[i*4];
			p[i*4].p2=pp[1+i*4];
			p[1+i*4].p1=pp[1+i*4];
			p[1+i*4].p2=pp[2+i*4];
			p[2+i*4].p1=pp[2+i*4];
			p[2+i*4].p2=pp[3+i*4];
			p[3+i*4].p1=pp[3+i*4];
			p[3+i*4].p2=pp[i*4];
cin>>h[i];
		}
	//	for(int i=0;i<4*n;i++)cout<<i<<" "<<segment_dis(p[i],path)<<endl;
		if(b==1){
			cout<<0<<endl;
			
		}
		else{
		double ue=1000.0,sita=0.0,me;
		for(int i=0;i<1000;i++){
			me=(ue+sita)/2.0;
			if(ch(me))sita=me;
			else ue=me;
		}
		printf("%.10lf\n",me);
		}
		
		
	}
	
	
	return 0;
}

Measured memory_bytes: 3196