Cod sursa(job #962265)

Utilizator a_h1926Heidelbacher Andrei a_h1926 Data 14 iunie 2013 12:47:26
Problema Nowhere-zero Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.34 kb
#include <cstdio>
#include <cmath>
#include <cassert>

#include <algorithm>
#include <vector>
#include <unordered_map>

using namespace std;

typedef long long int64;

class Point {
  public:
    double x, y;

    Point() {}

    Point(const double x, const double y) {
        this->x = x;
        this->y = y;
    }
};

class Edge {
  public:
    int x, y;

    Edge() {}

    Edge(const int x, const int y) {
        this->x = x;
        this->y = y;
    }

    bool operator==(const Edge &other) const {
        return (x == other.x && y == other.y);
    }

    class HashCode {
      public:
        int operator()(const Edge &object) const {
            return (1LL * object.x * Base + object.y) % U;
        }

      private:
        static const int Base = 100003;
        static const int U = 666013;
    };
};

vector<Point> Points;
vector<double> Alpha;
vector<vector<int>> G;
int V, E;
unordered_map<Edge, int, Edge::HashCode> Next;
vector<Edge> Edges;

class Compare {
  public:
    bool operator()(const int &x, const int &y) const {
        return Alpha[x] < Alpha[y];
    }
};

void BuildGraph() {
    for (int x = 0; x < V; ++x) {
        if (G[x].empty())
            continue;
        for (auto &y: G[x])
            Alpha[y] = atan2(Points[y].y - Points[x].y, Points[y].x - Points[x].x);
        sort(G[x].begin(), G[x].end(), Compare());
        G[x].push_back(G[x].front());
        for (int i = 0; i + 1 < static_cast<int>(G[x].size()); ++i)
            Next[Edge(G[x][i], x)] = G[x][i + 1];
    }
}

void Solve() {
    BuildGraph();
}

void Read() {
    assert(freopen("nowhere-zero.in", "r", stdin));
    assert(scanf("%d %d", &V, &E) == 2);
    G.resize(V);
    Points.resize(V);
    Alpha.resize(V);
    Edges.resize(E);
    for (int i = 0; i < V; ++i)
        assert(scanf("%lf %lf", &Points[i].x, &Points[i].y) == 2);
    for (int i = 0; i < E; ++i) {
        int x, y; assert(scanf("%d %d", &x, &y) == 2);
        --x; --y;
        Edges[i] = Edge(x, y);
        G[x].push_back(y); G[y].push_back(x);
    }
}

void Print() {
    assert(freopen("nowhere-zero.out", "w", stdout));
    for (int i = 0; i < E; ++i) {
        printf("%d %d %d\n", Edges[i].x + 1, Edges[i].y + 1, 0);
    }
}

int main() {
    Read();
    Solve();
    Print();
    return 0;
}