제출 #999580

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
999580		amine_aroua	통행료 (IOI18_highway)	C++17	90 / 100	226 ms	39200 KiB

highway

#include<bits/stdc++.h>
using namespace std;
#define intt long long
#define pb push_back
#define forr(i , x , y) for(int i = x; i <= y;i++)
#define fore(i , n) for(int i = 0 ; i < n;i++)
#define forn(i ,x , y) for(int i = x ; i >= y;i--)
long long ask(const vector<int> &w);
void answer(int s, int t);
const int MAXN = 90001;
intt a , b;
int n;
vector<pair<int ,int>> adj[MAXN];
vector<int> zeros , ones;
intt val;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
map<vector<int> , intt> mp;
intt myask(vector<int> v)
{
    if(mp.count(v))
        return mp[v];
    return mp[v] = ask(v);
}
int go(int root)
{
    vector<int> dist(n , n);
    vector<bool> vis(n , 0);
    dist[root] = 0;
    queue<int> q;
    q.push(root);
    while(!q.empty())
    {
        int x = q.front();
        q.pop();
        if(vis[x])
            continue;
        vis[x] = 1;
        for(auto [u , i] : adj[x])
        {
            if(dist[u] > dist[x] + 1)
            {
                dist[u] = dist[x] + 1;
                q.push(u);
            }
        }
    }
    vector<pair<int ,int>> nds;
    fore(i , n)
        nds.pb({dist[i] , i});
    sort(nds.rbegin() , nds.rend());
    int l = 0 , r = (int)nds.size();
    vector<int> asked = ones;
    while(l + 1 < r)
    {
        int mid = (l + r)/2;
        asked = zeros;
        forr(j , 0 , mid - 1) {
            for(auto i : adj[nds[j].second])asked[i.second] = 1;
        }
        if(myask(asked) == val)
            l = mid;
        else
            r = mid;
    }
    return nds[l].second;
}
void find_pair(int N, vector<int> U, vector<int> V, int A, int B)
{
    n = N;
    a = A , b = B;
    int m = (int)U.size();
    zeros.assign(m , 0);
    ones.assign(m , 1);
    fore(i , N)adj[i].clear();
    val = myask(zeros);
    fore(i , m)
    {
        adj[U[i]].pb({V[i] , i});
        adj[V[i]].pb({U[i] , i});
    }
    int S = go(go(0));
    answer(S , go(S));
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 6 / 6
• Subtask 4: 33 / 33
• Subtask 5: 18 / 18
• Subtask 6: 21 / 31