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 #include <iostream> #include <cmath> #include <vector> #include <algorithm> #include <iomanip> #include <cstring> #include <cstdio>
using namespace std; const double eps = 1e8; const double inf = 1e20; const double pi = acos(1.0); const int maxp = 1010;
int sgn(double x){ if(fabs(x) < eps)return 0; if(x < 0)return1; else return 1; }
inline double sqr(double x){return x*x;}
struct Point{ double x,y; Point(){} Point(double _x,double _y){ x = _x; y = _y; } void input(){ scanf("%lf%lf",&x,&y); } void output(){ printf("%.2f%.2f\n",x,y); } bool operator == (Point b)const{ return sgn(xb.x) == 0 && sgn(yb.y) == 0; } bool operator < (Point b)const{ return sgn(xb.x)== 0sgn(yb.y)?0:x<b.x; } Point operator(const Point &b)const{ return Point(xb.x,yb.y); } double operator ^(const Point &b)const{ return x*b.yy*b.x; } double operator *(const Point &b)const{ return x*b.x + y*b.y; } double len(){ return hypot(x,y); } double len2(){ return x*x + y*y; } double distance(Point p){ return hypot(xp.x,yp.y); } Point operator +(const Point &b)const{ return Point(x+b.x,y+b.y); } Point operator *(const double &k)const{ return Point(x*k,y*k); } Point operator /(const double &k)const{ return Point(x/k,y/k); } double rad(Point a,Point b){ Point p = *this; return fabs(atan2( fabs((ap)^(bp)),(ap)*(bp) )); } Point trunc(double r){ double l = len(); if(!sgn(l))return *this; r /= l; return Point(x*r,y*r); } Point rotleft(){ return Point(y,x); } Point rotright(){ return Point(y,x); } Point rotate(Point p,double angle){ Point v = (*this)p; double c = cos(angle), s = sin(angle); return Point(p.x + v.x*cv.y*s,p.y + v.x*s + v.y*c); } }; struct Line{ Point s,e; Line(){} Line(Point _s,Point _e){ s = _s; e = _e; } bool operator ==(Line v){ return (s == v.s)&&(e == v.e); } Line(Point p,double angle){ s = p; if(sgn(anglepi/2) == 0){ e = (s + Point(0,1)); } else{ e = (s + Point(1,tan(angle))); } } Line(double a,double b,double c){ if(sgn(a) == 0){ s = Point(0,c/b); e = Point(1,c/b); } else if(sgn(b) == 0){ s = Point(c/a,0); e = Point(c/a,1); } else{ s = Point(0,c/b); e = Point(1,(ca)/b); } } void input(){ s.input(); e.input(); } void adjust(){ if(e < s){ swap(s,e); } } double length(){ return s.distance(e); } double angle(){ double k = atan2(e.ys.y,e.xs.x); if(sgn(k) < 0)k += pi; if(sgn(kpi) == 0)k= pi; return k; } int relation(Point p){ int c = sgn((ps)^(es)); if(c < 0)return 1; else if(c > 0)return 2; else return 3; } bool pointonseg(Point p){ return sgn((ps)^(es)) == 0 && sgn((ps)*(pe)) <= 0; } bool parallel(Line v){ return sgn((es)^(v.ev.s)) == 0; } int segcrossseg(Line v){ int d1 = sgn((es)^(v.ss)); int d2 = sgn((es)^(v.es)); int d3 = sgn((v.ev.s)^(sv.s)); int d4 = sgn((v.ev.s)^(ev.s)); if( (d1^d2)==2 && (d3^d4)==2 )return 2; return (d1==0 && sgn((v.ss)*(v.se))<=0)  (d2==0 && sgn((v.es)*(v.ee))<=0)  (d3==0 && sgn((sv.s)*(sv.e))<=0)  (d4==0 && sgn((ev.s)*(ev.e))<=0); } int linecrossseg(Line v){ int d1 = sgn((es)^(v.ss)); int d2 = sgn((es)^(v.es)); if((d1^d2)==2) return 2; return (d1==0d2==0); } int linecrossline(Line v){ if((*this).parallel(v)) return v.relation(s)==3; return 2; } Point crosspoint(Line v){ double a1 = (v.ev.s)^(sv.s); double a2 = (v.ev.s)^(ev.s); return Point((s.x*a2e.x*a1)/(a2a1),(s.y*a2e.y*a1)/(a2a1 )); } double dispointtoline(Point p){ return fabs((ps)^(es))/length(); } double dispointtoseg(Point p){ if(sgn((ps)*(es))<0  sgn((pe)*(se))<0) return min(p.distance(s),p.distance(e)); return dispointtoline(p); } double dissegtoseg(Line v){ return min(min(dispointtoseg(v.s),dispointtoseg(v.e)),min(v.dispointtoseg(s),v.dispointtoseg(e))); } Point lineprog(Point p){ return s + ( ((es)*((es)*(ps)))/((es).len2()) ); } Point symmetrypoint(Point p){ Point q = lineprog(p); return Point(2*q.xp.x,2*q.yp.y); } };
int main(){ int t; cin>>t; while(t){ Line a,b; cin>>a.s.x>>a.s.y>>a.e.x>>a.e.y>>b.s.x>>b.s.y>>b.e.x>>b.e.y; double ans=0.0; if(a.segcrossseg(b)==0) ans=a.dissegtoseg(b); cout<<fixed<<setprecision(10)<<ans<<"\n"; } return 0; }
