oj.uz

Submission #649830

# Submission time Handle Problem Language Result Execution time Memory
649830 2022-10-11T11:40:31 Z welleyth Joker (BOI20_joker) C++17
25 / 100
 436 ms 26012 KB 
#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;

//#define int long long
#define pb push_back
#define mp make_pair

#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

constexpr int N = (int)2e5 + 111;
constexpr int md = (int)2e5 + 111;

mt19937 rnd(time(nullptr));

vector<int> g[N];
bool used[2][N];
bool c[2][N];

bool dfs(int v,int r,int pr = -1){
    used[r][v] = true;
    c[r][v] = true;
    for(auto& to : g[v]){
        if(pr == to)
            continue;
        if(used[r^1][to]){
            if(c[r][v]&c[r][to])
                return true;
            continue;
        }
        c[r^1][to] = true;
        if(dfs(to,r^1,v))
            return true;
    }
    return false;
}

int n,m,q;
vector<pair<int,int>> edges;

bool can(int l,int r){
    for(int j = 0; j <= n; j++){
        used[0][j] = false;
        used[1][j] = false;
        c[0][j] = c[1][j] = 0;
        g[j].clear();
    }
    bool have = false;
    for(int j = 0; j < l-1; j++){
        auto&[a,b] = edges[j];
        g[a].pb(b);
        g[b].pb(a);
    }
    for(int j = r; j < m; j++){
        auto&[a,b] = edges[j];
        g[a].pb(b);
        g[b].pb(a);
    }
    for(int j = 1; j <= n; j++){
        if(!used[0][j] && !used[1][j]){
            c[0][j] = 1;
            if(dfs(j,0)){
                return true;
            }
        }
    }
    return false;
}

void solve(){
    cin >> n >> m >> q;

    for(int i = 0; i < m; i++){
        int a,b;
        cin >> a >> b;
        edges.pb(mp(a,b));
    }

    bool answer[q];
    bool f = true;
    if(!can(1,0))
        f = false;

    vector<pair<int,int>> Queries[m+1];

    for(int i = 0; i < q; i++){
        int l,r;
        cin >> l >> r;
        if(!f){
            cout << "NO\n";
            continue;
        }
        Queries[l].pb(mp(r,i));
    }
    if(!f)
        return;
    for(int i = 0; i <= m; i++){
        if(Queries[i].empty())
            continue;
        sort(Queries[i].rbegin(),Queries[i].rend());
        if(!can(i,i)){
            for(auto&[r,id] : Queries[i]){
                answer[id] = 0;
            }
            continue;
        }
        int L = i, R = m;
        while(R - L > 1){
            int mid = (L+R)>>1;
            if(can(i,mid))
                L = mid;
            else
                R = mid;
        }
        for(auto&[r,id] : Queries[i]){
            if(r <= L)
                answer[id] = 1;
            else
                answer[id] = 0;
        }
    }

    for(int i = 0; i < q; i++){
        cout << (answer[i] ? "YES" : "NO") << "\n";
    }

    return;
}

signed main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
//    init();
    int tests = 1;
//    cin >> tests;
    for(int test = 1; test <= tests; test++){
//        cerr << "test = " << test << "\n";
        solve();
    }
    return 0;
}
/**
6 8 2
1 3
1 5
1 6
2 5
2 6
3 4
3 5
5 6
4 7
4 8

**/

Compilation message

Joker.cpp: In function 'bool can(int, int)':
Joker.cpp:52:10: warning: unused variable 'have' [-Wunused-variable]
   52 |     bool have = false;
      |          ^~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Incorrect 3 ms 4948 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Incorrect 3 ms 4948 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 274 ms 26012 KB Output is correct
4 Correct 112 ms 19068 KB Output is correct
5 Correct 182 ms 22208 KB Output is correct
6 Correct 224 ms 20160 KB Output is correct
7 Correct 228 ms 19116 KB Output is correct
8 Correct 196 ms 20672 KB Output is correct
9 Correct 240 ms 20888 KB Output is correct
10 Correct 436 ms 20896 KB Output is correct
11 Correct 207 ms 19100 KB Output is correct
12 Correct 316 ms 20552 KB Output is correct
13 Correct 175 ms 18416 KB Output is correct
14 Correct 204 ms 20504 KB Output is correct
15 Correct 318 ms 20204 KB Output is correct
16 Correct 412 ms 20868 KB Output is correct

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Incorrect 3 ms 4948 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #5
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Incorrect 3 ms 4948 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #6
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 3 ms 4948 KB Output is correct
4 Incorrect 3 ms 4948 KB Output isn't correct
5 Halted 0 ms 0 KB -