Submission #640889

#	Time	Username	Problem	Language	Result	Execution time	Memory
640889		pls33	Monthly railway pass (LMIO18_menesinis_bilietas)	C++17	100 / 100	250 ms	30768 KiB

menesinis_bilietas

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

#pragma region dalykai
using p32 = pair<int, int>;
using p32u = pair<uint32_t, uint32_t>;
using p64 = pair<int64_t, int64_t>;
using p64u = pair<uint64_t, uint64_t>;
using vi16 = vector<int16_t>;
using vi16u = vector<uint16_t>;
using vi32 = vector<int>;
using vi32u = vector<uint32_t>;
using vi64 = vector<int64_t>;
using vi64u = vector<uint64_t>;
using vp32 = vector<p32>;
using vp32u = vector<p32u>;
using vp64 = vector<p64>;
using vp64u = vector<p64u>;
using vvi32 = vector<vi32>;
using vvi32u = vector<vi32u>;
using vvi64 = vector<vi64>;
using vvi64u = vector<vi64u>;
using vvp32 = vector<vp32>;
using vvp32u = vector<vp32u>;
using vvp64 = vector<vp64>;
using vvp64u = vector<vp64u>;

using pf32 = pair<float, float>;
using pf64 = pair<double, double>;
using pf80 = pair<long double, long double>;
using vf32 = vector<float>;
using vf64 = vector<double>;
using vf80 = vector<long double>;
using vpf32 = vector<pf32>;
using vpf64 = vector<pf64>;
using vpf80 = vector<pf80>;
using vvf32 = vector<vf32>;
using vvf64 = vector<vf64>;
using vvf80 = vector<vf80>;
using vvpf32 = vector<vpf32>;
using vvpf64 = vector<vpf64>;
using vvpf80 = vector<vpf80>;

template <typename key, typename val>
using ord_map = tree<key, val, less<key>, rb_tree_tag,
                     tree_order_statistics_node_update>;

template <typename key>
using ord_set = tree<key, null_type, less<key>, rb_tree_tag,
                     tree_order_statistics_node_update>;

const int BUF_SZ = 1 << 15;
inline namespace fast_in
{
    char buf[BUF_SZ];
    int pos;
    int len;

    char next_char(FILE *f)
    {
        if (pos == len)
        {
            pos = 0;
            len = (int)fread(buf, 1, BUF_SZ, f);

            if (!len)
            {
                return EOF;
            }
        }

        return buf[pos++];
    }

    int read_int(FILE *f)
    {
        int x;
        char ch;
        int sgn = 1;

        while (!isdigit(ch = next_char(f)))
        {
            if (ch == '-')
            {
                sgn *= -1;
            }
        }

        x = ch - '0';
        while (isdigit(ch = next_char(f)))
        {
            x = x * 10 + (ch - '0');
        }

        return x * sgn;
    }
}

/**
 * @brief gale programos flush_out kviest!!
 */
inline namespace fast_out
{
    char buf[BUF_SZ];
    int pos;

    void flush_out(FILE *f)
    {
        fwrite(buf, 1, pos, f);
        pos = 0;
    }

    void write_char(char c, FILE *f)
    {
        if (pos == BUF_SZ)
        {
            flush_out(f);
        }

        buf[pos++] = c;
    }

    void write_int(int x, FILE *f)
    {
        static char num_buf[100];

        if (x < 0)
        {
            write_char('-', f);
            x *= -1;
        }

        int len = 0;
        for (; x >= 10; x /= 10)
        {
            num_buf[len++] = (char)('0' + (x % 10));
        }

        write_char((char)('0' + x), f);
        while (len)
        {
            write_char(num_buf[--len], f);
        }
        write_char('\n', f);
    }
}
#pragma endregion

struct dsu_t
{
    vi32 parent, rank;

    dsu_t(int n) : parent(n), rank(n, 1)
    {
        iota(parent.begin(), parent.end(), 0);
    }

    int find(int i)
    {
        if (parent[i] == i)
        {
            return i;
        }

        return parent[i] = find(parent[i]);
    }

    void set_union(int a, int b)
    {
        a = find(a);
        b = find(b);
        if (a == b)
        {
            return;
        }

        if (rank[b] > rank[a])
        {
            swap(a, b);
        }

        parent[b] = a;
        rank[a] += rank[b];
    }
};

int main()
{
#ifndef _AAAAAAAAA
    ios_base::sync_with_stdio(false);
    cin.tie(0);
#else
    freopen("bilietas.in", "r", stdin);
#ifndef __linux__
    atexit([]()
           {
        freopen("con", "r", stdin);
        system("pause"); });
#endif
#endif

    int v, e;
    cin >> v >> e;

    dsu_t dsu(v);
    vp32 bus;
    for (size_t i = 0; i < e; i++)
    {
        int a, b;
        char type;
        cin >> a >> b >> type;

        a--;
        b--;

        if (type == 'A')
        {
            bus.emplace_back(a, b);
        }
        else
        {
            dsu.set_union(a, b);
        }
    }

    vvi32 adj(v);
    bool used_bus = true;
    for (auto &b : bus)
    {
        b.first = dsu.find(b.first);
        b.second = dsu.find(b.second);
        if (b.first == b.second)
        {
            continue;
        }

        used_bus = false;
        adj[b.first].push_back(b.second);
        adj[b.second].push_back(b.first);
    }

    if (used_bus)
    {
        bool connected = true;
        for (auto &p : dsu.parent)
        {
            if (dsu.find(p) != dsu.parent.front())
            {
                connected = false;
                break;
            }
        }

        v = connected ? v : 0;
        cout << v << '\n';

        return 0;
    }

    int count = 0;
    for (int i = 0; i < adj.size(); i++)
    {
        auto &next = adj[i];
        if (next.size())
        {
            sort(next.begin(), next.end());

            auto it = unique(next.begin(), next.end());
            next.erase(it, next.end());

            int cur = dsu.rank[i];
            for (auto &a : next)
            {
                cur += dsu.rank[a];
            }

            count += (cur == v) * dsu.rank[i];
        }
    }

    cout << count << '\n';

    return 0;
}

Compilation message (stderr)

menesinis_bilietas.cpp:8: warning: ignoring '#pragma region dalykai' [-Wunknown-pragmas]
    8 | #pragma region dalykai
      | 
menesinis_bilietas.cpp:151: warning: ignoring '#pragma endregion ' [-Wunknown-pragmas]
  151 | #pragma endregion
      | 
menesinis_bilietas.cpp: In function 'int main()':
menesinis_bilietas.cpp:211:26: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  211 |     for (size_t i = 0; i < e; i++)
      |                        ~~^~~
menesinis_bilietas.cpp:265:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  265 |     for (int i = 0; i < adj.size(); i++)
      |                     ~~^~~~~~~~~~~~

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