Cod sursa(job #402416)

Utilizator DraStiKDragos Oprica DraStiK Data 23 februarie 2010 20:52:03
Problema Adapost Scor 40
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.17 kb
#include <algorithm>
#include <vector>
#include <bitset>
#include <cmath>
using namespace std;

#define pb push_back
#define DIM 805

struct punct {double x,y;} a[DIM>>1],v[DIM>>1];
double d[DIM][DIM],w[DIM*DIM];
vector <int> g[DIM];
int l[DIM],r[DIM];
bitset <DIM> viz;
int n,sol;

void read ()
{
    int i;

    scanf ("%d",&n);
    for (i=1; i<=n; ++i)
        scanf ("%lf%lf",&a[i].x,&a[i].y);
    for (i=1; i<=n; ++i)
        scanf ("%lf%lf",&v[i].x,&v[i].y);
}

void init ()
{
    int i,j,k;

    k=0;
    for (i=1; i<=n; ++i)
        for (j=1; j<=n; ++j)
            d[i][j]=w[++k]=sqrt ((a[i].x-v[j].x)*(a[i].x-v[j].x)+(a[i].y-v[j].y)*(a[i].y-v[j].y));
}

int pair_up (int nod)
{
    int i;

    if (viz[nod])
        return 0;
    viz[nod]=1;
    for (i=0; i<(int)g[nod].size (); ++i)
        if (!r[g[nod][i]])
        {
            l[nod]=g[nod][i];
            r[g[nod][i]]=nod;
            return 1;
        }
    for (i=0; i<(int)g[nod].size (); ++i)
        if (pair_up (r[g[nod][i]]))
        {
            l[nod]=g[nod][i];
            r[g[nod][i]]=nod;
            return 1;
        }
    return 0;
}

int cuplaj (double val)
{
    int i,j,ok,cup;

    for (i=1; i<=n; ++i)
    {
        g[i].clear ();
        for (j=1; j<=n; ++j)
            if (d[i][j]<=val)
                g[i].pb (j);
    }
    cup=0;
    memset (l,0,sizeof (l));
    memset (r,0,sizeof (r));
    do
    {
        ok=0;
        viz.reset ();
        for (i=1; i<=n; ++i)
            if (!l[i] && pair_up (i))
            {
                ok=1;
                ++cup;
            }
    }
    while (ok);
    if (cup!=n)
        return 0;
    return 1;
}

void solve ()
{
    int st,dr,mij;

    sol=n*n;
    sort (w+1,w+n*n+1);
    for (st=1, dr=n*n; st<=dr; )
    {
        mij=(st+dr)/2;
        if (cuplaj (w[mij]))
        {
            sol=mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }
    printf ("%lf 0",w[sol]);
}

int main ()
{
    freopen ("adapost.in","r",stdin);
    freopen ("adapost.out","w",stdout);

    read ();
    init ();
    solve ();

    return 0;
}