Submission #826466

#	Time	Username	Problem	Language	Result	Execution time	Memory
826466		ALeonidou	Highway Tolls (IOI18_highway)	C++17	51 / 100	212 ms	10964 KiB

highway

#include <bits/stdc++.h>
#include "highway.h"
    
using namespace std;
    
#define ll int
typedef vector <ll> vi;
typedef pair <ll,ll > ii;
typedef vector <ii> vii;
#define sz(x) (ll)x.size()
#define pb push_back
#define F first
#define S second
#define MID ((l+r)/2)
#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;
    
void tabb(ll n){
    for (ll i= 0; i<n; i++) cout<<"\t";
}
    
void printVct(vi &v){
    for (ll i=0; i<sz(v); i++){
        cout<<v[i]<<" ";
    }
    cout<<endl;
}
    
void printVctPair(vii &v){
    for (ll i=0; i<sz(v); i++){
        cout<<"("<<v[i].F<<","<<v[i].S<<") ";
    }
    cout<<endl;
}
    
void printVct2D(vector<vi> &adj){
    for (ll i=0; i<sz(adj); i++){
        cout<<i<<": ";
        for (ll j =0; j<sz(adj[i]); j++){
            cout<<"("<<adj[i][j]<<"),";
        }
        cout<<endl;
    }
    cout<<endl;
}
    
void printVctPair2D(vector<vii> &adj){
    for (ll i=0; i<sz(adj); i++){
        for (ll j =0; j<sz(adj[i]); j++){
            cout<<"("<<adj[i][j].F<<","<<adj[i][j].S<<"),";
        }
        cout<<endl;
    }
    cout<<endl;
}
    
vector <vii> adj;
ll n,m;
long long b;   //all light case value

ll solve(ll root){
    queue <ll> q;
    vii dis(n);
    for (ll i =0; i<n; i++)
        dis[i] = ii(-1, i);
    dis[root].F = 0;
    vi par(n, -1);
    q.push(root);
    while (!q.empty()){
        ll u= q.front();
        q.pop();
        for (ll i = 0; i<sz(adj[u]); i++){
            if (dis[adj[u][i].F].F == -1){
                q.push(adj[u][i].F);
                dis[adj[u][i].F].F = dis[u].F + 1;
                par[adj[u][i].F] = adj[u][i].S;
            }
        }
    }

    sort(dis.rbegin(), dis.rend());
    // cout<<"dis:";
    // printVctPair(dis);
    // cout<<"par:";
    // printVct(par);

    vi v;
    ll l = 0, r = n-1, mid;
    while (l < r){
        mid = MID;
        // dbg3(l,r,mid);

        v.assign(m, 0);
        // printVct(v);
        for (ll i= 0; i<=mid; i++){
            ll tmp = par[dis[i].S];
            if (tmp != -1) v[tmp] = 1;
        }

        long long c =ask(v);

        if (c > b){
            r = mid;
        }
        else{
            l = mid+1;
        }
    }            
    return dis[l].S;
}
    
void find_pair(int N, vi V, vi U, int A,int B) {
    n = N; m = sz(U);
    adj.assign(n, vii());
    for (ll i=0; i<m ;i++){
        adj[U[i]].pb(ii(V[i], i));
        adj[V[i]].pb(ii(U[i], i));
    }
    vi v(m, 0);  
    b = ask(v);
    
    ll l = 0, r = m-1, mid;
    while (l < r){
        mid = MID;
        v.assign(m, 0);
        for (ll i = 0; i<=mid; i++) 
            v[i] = 1;
        long long c = ask(v);
        if (c > b) r = mid;
        else l = mid+1;
    }
    ll p = U[l];
    // dbg(p);
    
    ll s = solve(p);
    // dbg(s);
    // cout<<endl<<endl<<endl;
    ll t = solve(s);
    //dbg2(s,t);
    answer(s, t);
}
    
/*
14 13 2 5 0 13
0 1
1 5
1 2
2 3
1 4
5 7
7 8
5 6
3 12
3 11
2 9
9 10
9 13

14 13 2 5 3 10
0 1
1 5
1 2
2 3
1 4
5 7
7 8
5 6
3 12
3 11
2 9
9 10
9 13
    
*/

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 6 / 6
• Subtask 4: 33 / 33
• Subtask 5: 0 / 18
• Subtask 6: 0 / 31