Submission #1054241

#	Time	Username	Problem	Language	Result	Execution time	Memory
1054241		Mighilon	Joker (BOI20_joker)	C++17	0 / 100	2043 ms	12944 KiB

Joker

#include <bits/stdc++.h>
using namespace std;
 
#ifdef DEBUG
#include "../Library/debug.h"
#else
#define dbg(x...)
// #define cin fin
// #define cout fout
// const string FILE_NAME = ""; ifstream fin(FILE_NAME + ".in"); ofstream fout(FILE_NAME + ".out");
#endif
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
 
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) for (int i = 0; i < (a); ++i)
#define FORd(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define F0Rd(i, a) for (int i = (a) - 1; i >= 0; --i)
#define trav(a, x) for (auto& a : x)
#define f first 
#define s second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) x.begin(), x.end()
 
const char nl = '\n';
const int INF = 1e9;
const int MOD = 1e9 + 7;

vector<vi> adj;
vi edges, good;
vi vis, dist;

bool cycle = false;
void dfs(int u, int p, int d){
    if(vis[u] == 2)
        return;
    if(vis[u] == 1){
        if(abs(dist[u] - d) % 2 == 0)
            return;
        cycle = true;
        return;
    }
    vis[u] = 1;
    dist[u] = d;
    trav(id, adj[u]){
        if(!good[id]) continue;
        int v = edges[id] ^ u;
        if(v == p)
            continue;
        dfs(v, u, d + 1);
    }
    vis[u] = 2;
}

void solve(){
    int n, m, q;
    cin >> n >> m >> q;
    adj.resize(n);
    edges.resize(m);
    F0R(i, m){
        int a, b;
        cin >> a >> b;
        --a, --b;
        edges[i] = a ^ b;
        adj[a].pb(i);
        adj[b].pb(i);
    }
    vis.resize(n);
    good.resize(m);
    while(q--){
        int a, b;
        cin >> a >> b;
        a--, b--;
        vis = vector<int>(n, 0);
        dist = vector<int>(n, 0);
        F0R(i, m){
            if(i >= a && i <= b)
                good[i] = false;
            else good[i] = true;
        }
        cycle = false;
        F0R(i, n){
            if(vis[i] == 0)
                dfs(0, -1, 1);
        }
        if(cycle)
            cout << "YES\n";
        else cout << "NO\n";
        dbg(cycle)
        dbg(dist)
        dbg(vis)
    }
}
 
int32_t main(){
    ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
    
    int TC = 1;
    // cin >> TC;
    while(TC--){
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 8
• Subtask 3: 0 / 25
• Subtask 4: 0 / 10
• Subtask 5: 0 / 22
• Subtask 6: 0 / 29