【最短路】【Heap-dijkstra】Gym - 101147B - Street

#include<cstdio>
#include<algorithm>
#include<queue>
#include<cmath>
#include<cstring>
using namespace std;
#define EPS 0.00000001
#define N 109
int T,n,H,X;
int hs
,xs
,ds
;
bool is
;
double sqr(int x)
{
return (double)x*(double)x;
}
int e,v[N*N*4],first
,next[N*N*4];
double w[N*N*4];
void AddEdge(int U,int V,double W)
{
v[++e]=V;
w[e]=W;
next[e]=first[U];
first[U]=e;
}
double d
;
bool vis
;
struct Point{double d;int u;
Point(const double &X,const int &Y){d=X;u=Y;}
Point(){}};
bool operator < (Point a,Point b){return a.d>b.d;}
priority_queue<Point>q;
void dijkstra(int S)
{
for(int i=1;i<=n+2;++i) d[i]=1000000007.0;
d[S]=0; q.push(Point(0.0,S));
while(!q.empty())
{
Point x=q.top(); q.pop();
if(!vis[x.u])
{
vis[x.u]=1;
for(int i=first[x.u];i;i=next[i])
if(d[v[i]]-d[x.u]-w[i]>EPS)
{
d[v[i]]=d[x.u]+w[i];
q.push(Point(d[v[i]],v[i]));
}
}
}
}
int main()
{
freopen("street.in","r",stdin);
scanf("%d",&T);
for(;T;--T)
{
memset(v,0,sizeof(v));
memset(first,0,sizeof(first));
memset(w,0,sizeof(w));
memset(next,0,sizeof(next));
memset(vis,0,sizeof(vis));
e=0;
scanf("%d%d%d",&n,&H,&X);
for(int i=1;i<=n;++i)
scanf("%d%d%d%d",&hs[i],&xs[i],&ds[i],&is[i]);
for(int i=1;i<=n;++i)
for(int j=i+1;j<=n;++j)
if(is[i]==is[j] || (is[i]!=is[j] && xs[i]+xs[j]>X))
{
AddEdge(i,j,ds[j]-(ds[i]+hs[i])>=0 ? ds[j]-(ds[i]+hs[i]) : ds[i]-(ds[j]+hs[j]));
AddEdge(j,i,ds[j]-(ds[i]+hs[i])>=0 ? ds[j]-(ds[i]+hs[i]) : ds[i]-(ds[j]+hs[j]));
}
else if((ds[i]+hs[i]>=ds[j] && ds[i]<=ds[j]+hs[j]) ||
(ds[j]+hs[j]>=ds[i] && ds[j]<=ds[i]+hs[i]))
{
AddEdge(i,j,X-(xs[i]+xs[j]));
AddEdge(j,i,X-(xs[i]+xs[j]));
}
else if(ds[i]+hs[i]<ds[j])
{
AddEdge(i,j,sqrt(sqr(ds[j]-(ds[i]+hs[i]))+sqr(X-(xs[i]+xs[j]))));
AddEdge(j,i,sqrt(sqr(ds[j]-(ds[i]+hs[i]))+sqr(X-(xs[i]+xs[j]))));
}
else
{
AddEdge(i,j,sqrt(sqr(ds[i]-(ds[j]+hs[j]))+sqr(X-(xs[i]+xs[j]))));
AddEdge(j,i,sqrt(sqr(ds[i]-(ds[j]+hs[j]))+sqr(X-(xs[i]+xs[j]))));
}
for(int i=1;i<=n;++i)
{
AddEdge(n+1,i,ds[i]);
AddEdge(i,n+1,ds[i]);
AddEdge(i,n+2,H-(ds[i]+hs[i]));
AddEdge(n+2,i,H-(ds[i]+hs[i]));
}
dijkstra(n+1);
printf("%.6lf\n",d[n+2]);
}
return 0;
}