Submission #498242

#	Time	Username	Problem	Language	Result	Execution time	Memory
498242		aurims	Monthly railway pass (LMIO18_menesinis_bilietas)	C++14	100 / 100	721 ms	40096 KiB

menesinis_bilietas

#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>

using namespace std;

struct vertex {
    int group;               // kokiai jungumo komponenciu grupei priklauso
    vector<int> train_edges; // su kokiais miestais turi traukini
    vector<int> bus_edges;   // su kokiais miestais turi autika
    bool visited;            // ar aplankyta

    vertex(): group(-1), visited(false) {} // by default, neaplankyta ir nepriklauso jokiai jung. komp. grupei
};
vector<vertex> map;

// visas virsunes jungumo komponenteje priskiriam vienai grupei
void paint_graph(int idx, int colour) {
    assert(map[idx].group == -1);

    vertex& v = map[idx];
    v.group = colour; // priskiriam miesta prie grupes

    for (const int& sidx : v.train_edges) {
        assert(0 <= sidx && sidx < map.size());

        vertex& sibling = map[sidx];

        if (sibling.group != -1) // jei kaimynas turi grupe, tai skipinam ji
            continue;

        paint_graph(sidx, colour); // nuspalvinam kaimyna
    }
}

int find_adjacent_comps(int idx, vector<bool>& adjacent) {
    assert(!map[idx].visited);
    vertex& v = map[idx];
    v.visited = true;

    int size = 1;

    for (const int& sidx : v.bus_edges) {
        assert(0 <= sidx && sidx < map.size());

        vertex& sibling = map[sidx];
        adjacent[sibling.group] = true;
    }

    for (const int& sidx : v.train_edges) {
        assert(0 <= sidx && sidx < map.size());

        vertex& sibling = map[sidx];

        if (sibling.visited)
            continue;

        size += find_adjacent_comps(sidx, adjacent);
    }

    return size;
}

int find_full_comp_size(int idx, int groups) {
    vector<bool> bitset(groups, false); // jungumo komponenciu aplankymo sarasas
    bitset[map[idx].group] = true; // Always visit yourself

    int size = find_adjacent_comps(idx, bitset);

    for (int i = 0; i < groups; i++)
        if (!bitset[i]) // jei yra neaplankyta jungumo komponente, tai vadinasi is miesto map[idx] neina aplankyt visu miestu pigiai
            return 0;

    return size;
}

int main(int argc, const char * argv[]) {
    ios::sync_with_stdio(false), cin.tie(0);
    int n, m;
    cin >> n >> m;
    map.resize(n);
    for (int i = 0; i < m; i++) { // iteruojam per transporto linijas
        int a, b;
        char c;
        cin >> a >> b >> c;
        if (c == 'T') { // jei jungia traukinys
            // grafe sujungiam tas dvi virsunes
            map[a-1].train_edges.push_back(b-1);
            map[b-1].train_edges.push_back(a-1);
        } else { // jei jungia autikas
            // grafe sujungiam tas dvi virsunes
            map[a-1].bus_edges.push_back(b-1);
            map[b-1].bus_edges.push_back(a-1);
        }
    }

    int group = 0;
    for (int i = 0; i < n; i++) // iteruojam per miestus
        if (map[i].group == -1) // jeigu tas miestas dar nepriklauso jokiai grupei
            paint_graph(i, group++); // tai priskiriam ji kokiai grupei

    int size = 0;
    for (int i = 0; i < n; i++)
        if (!map[i].visited)
            size += find_full_comp_size(i, group);

    cout << size << endl;

    return 0;
}

Compilation message (stderr)

In file included from /usr/include/c++/10/cassert:44,
                 from menesinis_bilietas.cpp:4:
menesinis_bilietas.cpp: In function 'void paint_graph(int, int)':
menesinis_bilietas.cpp:26:34: warning: comparison of integer expressions of different signedness: 'const int' and 'std::vector<vertex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |         assert(0 <= sidx && sidx < map.size());
      |                             ~~~~~^~~~~~~~~~~~
menesinis_bilietas.cpp: In function 'int find_adjacent_comps(int, std::vector<bool>&)':
menesinis_bilietas.cpp:45:34: warning: comparison of integer expressions of different signedness: 'const int' and 'std::vector<vertex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |         assert(0 <= sidx && sidx < map.size());
      |                             ~~~~~^~~~~~~~~~~~
menesinis_bilietas.cpp:52:34: warning: comparison of integer expressions of different signedness: 'const int' and 'std::vector<vertex>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |         assert(0 <= sidx && sidx < map.size());
      |                             ~~~~~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 6 / 6
• Subtask 3: 30 / 30
• Subtask 4: 35 / 35
• Subtask 5: 19 / 19