oj.uz

Submission #1049660

# Submission time Handle Problem Language Result Execution time Memory
1049660 2024-08-09T03:41:13 Z shiomusubi496 Joker (BOI20_joker) C++17
25 / 100
 141 ms 23484 KB 
#include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep2(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rrep(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
#define rrep2(i, a, b) for (int i = (int)(b) - 1; i >= (int)(a); --i)
#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)

using namespace std;

using ll = long long;

template<class T, class U> bool chmin(T& a, const U& b) { return a > b ? a = b, true : false; }
template<class T, class U> bool chmax(T& a, const U& b) { return a < b ? a = b, true : false; }

class UndoableUF {
    int n;
    bool flag = true;
    vector<int> par;
    vector<tuple<int, int, bool>> history;

public:
    UndoableUF(int n_) : n(n_ / 2), par(n_, -1) {}
    int find(int x) { return par[x] < 0 ? x : find(par[x]); }
    bool merge(int x, int y) {
        x = find(x), y = find(y);
        history.emplace_back(x, par[x], flag);
        history.emplace_back(y, par[y], flag);
        if (x == y) return false;
        if (par[x] > par[y]) swap(x, y);
        par[x] += par[y];
        par[y] = x;
        if (same(x, (x + n) % (2 * n))) flag = false;
        return true;
    }
    bool same(int x, int y) { return find(x) == find(y); }
    void undo() {
        auto [x, px, _] = history.back(); history.pop_back();
        auto [y, py, f] = history.back(); history.pop_back();
        par[x] = px;
        par[y] = py;
        flag = f;
    }
    void snapshot() { history.clear(); }
    void rollback() {
        while (!history.empty()) undo();
    }
    bool is_bip() { return flag; }
};

int main() {
    int N, M, Q; cin >> N >> M >> Q;
    vector<pair<int, int>> A(M);
    rep (i, M) {
        cin >> A[i].first >> A[i].second;
        --A[i].first, --A[i].second;
    }
    vector<array<int, 3>> B(Q);
    rep (i, Q) {
        cin >> B[i][0] >> B[i][1];
        --B[i][0];
        B[i][2] = i;
    }
    int block = 1;
    sort(all(B), [&](auto a, auto b) {
        if (a[0] / block != b[0] / block) return a[0] < b[0];
        return a[1] > b[1];
    });
    vector<bool> ans(Q);
    int curl = block, curr = M;
    UndoableUF uf(2 * N);
    for (auto [l, r, k] : B) {
        while (curl < l) {
            uf.rollback();
            rep2 (i, curl - block, curl) {
                if (i >= M) break;
                uf.merge(A[i].first, A[i].second + N);
                uf.merge(A[i].first + N, A[i].second);
            }
            uf.snapshot();
            curl += block;
            curr = M;
        }
        assert(curr >= r);
        rrep2 (i, r, curr) {
            uf.merge(A[i].first, A[i].second + N);
            uf.merge(A[i].first + N, A[i].second);
        }
        curr = r;
        rep2 (i, curl - block, l) {
            uf.merge(A[i].first, A[i].second + N);
            uf.merge(A[i].first + N, A[i].second);
        }
        ans[k] = uf.is_bip();
        rep2 (i, curl - block, l) uf.undo(), uf.undo();
    }
    rep (i, Q) puts(ans[i] ? "NO" : "YES");
}

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Runtime error 1 ms 348 KB Execution killed with signal 6
6 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Runtime error 1 ms 348 KB Execution killed with signal 6
6 Halted 0 ms 0 KB -

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 122 ms 20924 KB Output is correct
4 Correct 116 ms 22188 KB Output is correct
5 Correct 127 ms 22208 KB Output is correct
6 Correct 127 ms 23084 KB Output is correct
7 Correct 136 ms 22204 KB Output is correct
8 Correct 112 ms 21952 KB Output is correct
9 Correct 115 ms 21916 KB Output is correct
10 Correct 141 ms 22720 KB Output is correct
11 Correct 123 ms 22816 KB Output is correct
12 Correct 124 ms 22704 KB Output is correct
13 Correct 126 ms 22056 KB Output is correct
14 Correct 122 ms 21552 KB Output is correct
15 Correct 125 ms 22972 KB Output is correct
16 Correct 132 ms 23484 KB Output is correct

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Runtime error 1 ms 348 KB Execution killed with signal 6
6 Halted 0 ms 0 KB -

Subtask #5
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Runtime error 1 ms 348 KB Execution killed with signal 6
6 Halted 0 ms 0 KB -

Subtask #6
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Runtime error 1 ms 348 KB Execution killed with signal 6
6 Halted 0 ms 0 KB -