oj.uz

Submission #973267

# Submission time Handle Problem Language Result Execution time Memory
973267 2024-05-01T17:01:09 Z vladilius Joker (BOI20_joker) C++17
25 / 100
 297 ms 24900 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second

struct dsu{
    vector<pair<int&, int>> hist;
    vector<int> sz, p;
    vector<bool> f;
    int n, S, Sf;
    dsu(int ns){
        n = ns;
        p.resize(2 * n + 1);
        sz.resize(2 * n + 1);
        for (int i = 1; i <= 2 * n; i++){
            p[i] = i;
            sz[i] = 1;
        }
    }
    void save(){
        S = (int) hist.size();
        Sf = (int) f.size();
    }
    int get(int v){
        if (p[v] != v){
            return get(p[v]);
        }
        return v;
    }
    int op(int v){
        return v + n;
    }
    void roll_back(){
        while (hist.size() != S){
            hist.back().ff = hist.back().ss;
            hist.pop_back();
        }
        while (f.size() != Sf){
            f.pop_back();
        }
    }
    void unite(int x, int y){
        x = get(x); y = get(y);
        if (x == y) return;
        if (sz[x] > sz[y]) swap(x, y);
        hist.pb({p[x], p[x]});
        hist.pb({sz[y], sz[y]});
        p[x] = y;
        sz[y] += sz[x];
    }
    bool add(pii P){
        auto [x, y] = P;
        if (!x) return 0;
        unite(x, op(y));
        unite(y, op(x));
        bool k = ((!f.empty() && f.back()) | (get(x) == get(y)));
        f.pb(k);
        return k;
    }
};

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, M, q; cin>>n>>M>>q;
    vector<pii> ed = {{0, 0}};
    for (int i = 1; i <= M; i++){
        int u, v; cin>>u>>v;
        ed.pb({u, v});
    }
    dsu T(n);
    T.save();
    for (int i = 1; i <= M; i++){
        T.add(ed[i]);
    }
    if (!T.f.back()){
        for (int i = 1; i <= q; i++){
            cout<<"NO"<<"\n";
        }
        return 0;
    }
    T.roll_back();
    
    vector<int> last(M + 1);
    function<void(int, int, pii)> solve = [&](int l, int r, pii R){
        if (l > r) return;
        assert(R.ff <= R.ss);

        int m = (l + r) / 2;
        T.save();
        for (int i = l; i < m; i++){
            T.add(ed[i]);
        }
        int i = R.ss;
        while (T.f.empty() || !T.f.back()){
            T.add(ed[i--]);
        }
        last[m] = i;
        T.roll_back();
        
        T.save();
        for (int i = last[m] + 1; i <= R.ss; i++){
            T.add(ed[i]);
        }
        solve(l, m - 1, {R.ff, last[m]});
        T.roll_back();
        
        T.save();
        for (int i = l; i <= m; i++){
            T.add(ed[i]);
        }
        solve(m + 1, r, {last[m], R.ss});
        T.roll_back();
    };
    
    solve(1, M, {0, M});

    while (q--){
        int l, r; cin>>l>>r;
        cout<<((r <= last[l]) ? "YES" : "NO")<<"\n";
    }
}

Compilation message

Joker.cpp: In member function 'void dsu::roll_back()':
Joker.cpp:37:28: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int&, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   37 |         while (hist.size() != S){
      |                ~~~~~~~~~~~~^~~~
Joker.cpp:41:25: warning: comparison of integer expressions of different signedness: 'std::vector<bool>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   41 |         while (f.size() != Sf){
      |                ~~~~~~~~~^~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 169 ms 15928 KB Output is correct
4 Correct 51 ms 23976 KB Output is correct
5 Correct 196 ms 24132 KB Output is correct
6 Correct 193 ms 14408 KB Output is correct
7 Correct 197 ms 14136 KB Output is correct
8 Correct 268 ms 10756 KB Output is correct
9 Correct 288 ms 14600 KB Output is correct
10 Correct 278 ms 23836 KB Output is correct
11 Correct 218 ms 14148 KB Output is correct
12 Correct 215 ms 23876 KB Output is correct
13 Correct 256 ms 7700 KB Output is correct
14 Correct 281 ms 10832 KB Output is correct
15 Correct 297 ms 23104 KB Output is correct
16 Correct 277 ms 24900 KB Output is correct

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #5
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #6
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -