Submission #836400

#	Time	Username	Problem	Language	Result	Execution time	Memory
836400		ALeonidou	Thousands Islands (IOI22_islands)	C++17	1.75 / 100	28 ms	4156 KiB

islands

#include "islands.h"

#include <variant>
#include <bits/stdc++.h>

using namespace std;
#define ll int
#define sz(x) (ll)x.size()
#define F first
#define S second
#define MID ((l+r)/2)
#define pb push_back
#define dbg(x) cout<<#x<<": "<<x<<endl;
#define dbg2(x,y) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<endl;
#define dbg3(x,y,z) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<" "<<#z<<": "<<z<<endl;
#define dbg4(x,y,z,w) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<" "<<#z<<": "<<z<<" "<<#w<<": "<<w<<endl;
#define dbg5(x,y,z,w,q) cout<<#x<<": "<<x<<" "<<#y<<": "<<y<<" "<<#z<<": "<<z<<" "<<#w<<": "<<w<<" "<<#q<<": "<<q<<endl;
#define ins insert

typedef vector <ll> vi;
typedef pair <ll,ll> ii;
typedef vector <ii> vii;
#define MOD 1000002022
#define inf 1e9

vector <vi> adj;
vi vis, depth;

ll max_depth = 0;
void dfs(ll u, ll p = -1){
    vis[u] = 1;
    if (p == -1) depth[u] =0;
    else depth[u] = 1 + depth[p];
    max_depth = max(max_depth, depth[u]);
    for (ll i= 0; i<sz(adj[u]);i++){
        if (!vis[adj[u][i]]){
            dfs(adj[u][i], u);
        }
    }
}

variant<bool, vi> find_journey(int N, int M, vi U, vi V){
    ll n = N, m = M;
    ll c =0;
    adj.assign(n, vi());
    for (ll i=0; i<m;i++){
        adj[U[i]].pb(V[i]);
        if (U[i] == 0) c++;
    }

    if ( c>= 2) return true;

    vis.assign(n, 0);
    depth.resize(n);
    dfs(0);

    return (max_depth >= 2);
}

• Subtask 1: 0 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45