Cod sursa(job #64905)

Utilizator fireatmyselfBogdan-Alexandru Stoica fireatmyself Data 6 iunie 2007 10:28:21
Problema Adapost Scor 43
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.41 kb
#include <cstdio>
#include <cstring>
#include <cmath>
#include <vector>
#include <algorithm>


#define NMAX 404
#define INF 666000666
#define eps 1e-4
#define f first
#define s second

using namespace std;

int N, Cup[NMAX], F[NMAX];
vector<pair<double,int> > D[NMAX];
double X[NMAX], Y[NMAX], Rmin, Dmin, Dd[NMAX][NMAX];

void read()
{
        int i, j;
        double x, y;

        freopen("adapost.in", "r", stdin);
        scanf("%d", &N);

        for (i = 1; i <= N; i++)
            { scanf("%lf %lf", &X[i], &Y[i]); D[i].push_back(make_pair(-INF,0)); }

        for (i = 1; i <= N; i++)
        {
                scanf("%lf %lf", &x, &y);
                for (j = 1; j <= N; j++)
                {
                    D[j].push_back(make_pair(sqrt( (X[j]-x)*(X[j]-x) + (Y[j]-y)*(Y[j]-y) ), i));
                    Dd[j][i] = D[j][i].f;
                }
        }

        for (i = 1; i <= N; i++) sort(D[i].begin(), D[i].end());
}

int pairthembaby(int i, double dmax)
{
        int j, x;
        
        if (F[i]) return 0;
        F[i] = 1;
        for (j = 1; j <= N && D[i][j].f <= dmax; j++)
            if ((!Cup[ D[i][j].s ]) || (pairthembaby(Cup[D[i][j].s], dmax)))
            {
                x = i;
                if (Cup[ D[i][j].s ] > 0)
                   if (Dd[ Cup[ D[i][j].s ] ][ D[i][j].s ]<Dd[ i ][ D[i][j].s ])
                      x = Cup[ D[i][j].s ];
                Cup[ D[i][j].s ] = i;
                return 1;
            }
        return 0;
}

void joint(double dmax)
{
        int i;

        for (i = 1; i <= N; i++)
            if (!pairthembaby(i,dmax))
            {
                memset(F,0,sizeof(F));
                pairthembaby(i,dmax);
            }
}

void solve()
{
        int flow, i;
        double lo = 0, hi = (1<<28), mij, dist;

        while (lo<=hi)
        {
                mij = (lo+hi)/2.0;
                memset(Cup,0,sizeof(Cup));
                joint(mij);
                for (i = 1, dist = flow = 0; i <= N; i++)
                    dist += Dd[ Cup[i] ][i], flow += (Cup[i]>0);
                if (flow == N) Rmin = mij, Dmin = dist, hi = mij-eps;
                else lo = mij+eps;
        }
}

void write()
{
        freopen("adapost.out", "w", stdout);
        printf("%lf %lf\n", Rmin, Dmin);
}

int main()
{
        read();
        solve();
        write();
        return 0;
}