Submission #876149

# Submission time Handle Problem Language Result Execution time Memory
876149 2023-11-21T10:19:59 Z sleepntsheep Joker (BOI20_joker) C++17
0 / 100
45 ms 26160 KB
#include <cstdio>
#include <cstring>
#include <cassert>
#include <string>
#include <deque>
#include <vector>
#include <map>
#include <queue>
#include <algorithm>
#include <iostream>
#include <utility>
using namespace std;
using i64 = long long;
using f80 = long double;
#define ShinLena cin.tie(nullptr)->sync_with_stdio(false)

#define N 200005
#define ALL(x) x.begin(), x.end()

int n, m, q, ne, h[N], e[N][2], r[N+1];

struct dsu
{
    vector<int> p, pp, bi;
    vector<tuple<int, int, int, int, int, int, int>> save;
    int cb;
    dsu(int n) : p(n, -1), pp(n, 0), bi(n, 1), cb(n) {}
    int find(int x)
    {
        if (p[x] < 0) return p[x];
        auto X { find(p[x]) };
        if (p[x] >= 0) pp[x] = pp[p[x]] ^ 1;
        return X;
    }
    int unite(int x0, int y0)
    {
        int x { find(x0) } , y { find(y0) };
        if (x == y)
        {
            save.emplace_back(x, y, -1, pp[x], pp[x], bi[x], bi[x]);
            if (pp[x0] == pp[y0]) cb += (0 - bi[x]), bi[x] = 0;
            return 0;
        }
        if (-p[x] > -p[y]) swap(x, y);
        save.emplace_back(x, y, p[x], pp[x], pp[y], bi[x], bi[y]);
        pp[x] = pp[x0] ^ pp[y0] ^ 1;
        p[y] += p[x];
        p[x] = y;
        cb -= bi[y];
        bi[y] &= bi[x];
        cb += bi[y];
        return 1;
    }

    void rollback()
    {
        auto [x, y, px, ppx, ppy, bix, biy] = save.back(); save.pop_back();
        if (px != -1) p[y] -= (p[x] = px);
        pp[x] = ppx; pp[y] = ppy;
        cb -= bi[y] + bi[x];
        bi[y] = biy; bi[x] = bix;
        cb += bi[y] + bi[x];
    }
};

struct qdsu
{
    dsu ds;
    int bottom;
    struct upd { char type; int x, y; };
    vector<upd> S;

    qdsu(int n) : ds(n), bottom(0) {}

    void bottomify()
    {
        while (bottom < (int)S.size() && S[bottom].type == 'B') ++bottom;
    }

    void fix()
    {
        if (S.empty() || S.back().type == 'A') return;
        bottomify();
        deque<upd> s[2];
        for (int j = (int)S.size() - 1; (s[1].size() != s[0].size() || s[0].empty()) && j >= bottom; --j)
        {
            if (S[j].type == 'A') s[1].push_front(S[j]);
            else s[0].push_front(S[j]);
            ds.rollback();
            S.pop_back();
        }
        for (auto j : {0, 1}) for (auto x : s[j]) S.push_back(x), ds.unite(x.x, x.y);
        bottomify();
    }

    void new_phase()
    {
        for (auto i = S.size(); i--;) ds.rollback();
        for (auto i = S.size(); i--;) S[i].type = 'A', ds.unite(S[i].x, S[i].y);
        reverse(S.begin(), S.end());
        bottom = 0;
    }

    void pop()
    {
        bottomify();
        if (bottom == S.size()) new_phase();
        fix();
        S.pop_back();
        ds.rollback();
    }

    int unite(int x, int y)
    {
        S.push_back(upd{'B', x, y});
        return ds.unite(x, y);
    }
};

int main()
{
    ShinLena;
    cin >> n >> m >> q;
    for (int i = 0; i < m; ++i) cin >> e[i][0] >> e[i][1];
    qdsu qd(n);
    for (int i { m }; i--;) qd.unite(e[i][0], e[i][1]);

    for (int j = m - 1, i = m - 1; i >= -1; --i)
    {
        while (j > i && j >= 0)
        {
            if (qd.ds.cb)
            {
                r[i+1] = j;
                break;
            }
            else
            {
                qd.unite(e[j][0], e[j][1]);
                --j;
            }
        }
        qd.pop();
    }

    for (int i = 0, x, y; i < q; ++i) cin >> x >> y, cout << (r[x] >= y ? "YES\n" : "NO\n");

    return 0;
}


Compilation message

Joker.cpp: In member function 'void qdsu::pop()':
Joker.cpp:107:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<qdsu::upd>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |         if (bottom == S.size()) new_phase();
      |             ~~~~~~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 2 ms 4700 KB Execution killed with signal 6
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 2 ms 4700 KB Execution killed with signal 6
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 45 ms 26160 KB Execution killed with signal 11
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 2 ms 4700 KB Execution killed with signal 6
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 2 ms 4700 KB Execution killed with signal 6
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 0 ms 2396 KB Output is correct
3 Runtime error 2 ms 4700 KB Execution killed with signal 6
4 Halted 0 ms 0 KB -