oj.uz

Submission #973228

# Submission time Handle Problem Language Result Execution time Memory
973228 2024-05-01T16:27:38 Z vladilius Joker (BOI20_joker) C++17
25 / 100
 302 ms 25672 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();
    bool ind = false;
    for (int i = 1; i <= M; i++){
        ind = T.add(ed[i]);
    }
    if (!ind){
        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;

        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 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 456 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 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 456 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 0 ms 348 KB Output is correct
3 Correct 159 ms 15424 KB Output is correct
4 Correct 55 ms 23920 KB Output is correct
5 Correct 195 ms 24212 KB Output is correct
6 Correct 186 ms 15044 KB Output is correct
7 Correct 200 ms 16564 KB Output is correct
8 Correct 273 ms 11544 KB Output is correct
9 Correct 294 ms 16004 KB Output is correct
10 Correct 277 ms 24628 KB Output is correct
11 Correct 219 ms 15564 KB Output is correct
12 Correct 210 ms 25672 KB Output is correct
13 Correct 258 ms 8780 KB Output is correct
14 Correct 269 ms 11840 KB Output is correct
15 Correct 302 ms 22848 KB Output is correct
16 Correct 277 ms 24136 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 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 456 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 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 456 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 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Incorrect 0 ms 456 KB Output isn't correct
6 Halted 0 ms 0 KB -