Submission #1251698

#	Time	Username	Problem	Language	Result	Execution time	Memory
1251698		Zbyszek99	Obstacles for a Llama (IOI25_obstacles)	C++20	23 / 100	2101 ms	137988 KiB

obstacles

#include "obstacles.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9;

struct table
{
    pii min_[200001][18];
    pii max_[200001][18];
    void set(vi v)
    {
        rep(i,siz(v))
        {
            min_[i][0] = {v[i],i};
            max_[i][0] = {v[i],i};
        }
        rep2(bit,1,17)
        {
            rep(i,siz(v))
            {
                min_[i][bit] = min(min_[i][bit-1],(i+(1<<(bit-1)) < siz(v) ? min_[i+(1<<(bit-1))][bit-1] : (pii){1e9,1e9}));
                max_[i][bit] = max(max_[i][bit-1],(i+(1<<(bit-1)) < siz(v) ? max_[i+(1<<(bit-1))][bit-1] : (pii){-1e9,-1e9}));
            }
        }
    }
    pii get_max(int l, int r)
    {
        int lg = __lg(r-l+1);
        return max(max_[l][lg],max_[r-(1 << lg)+1][lg]);
    }
    pii get_min(int l, int r)
    {
        int lg = __lg(r-l+1);
        return min(min_[l][lg],min_[r-(1 << lg)+1][lg]);
    }
};

table tableX;
table tableY;
pii max_H[200001];
int X[200001];
int Y[200001];

void rek(int l, int r, int Hr, pii pop)
{
   // cerr << l << " " << r << " " << Hr << " " << pop.ff << " " << pop.ss << " rek\n";
    if(l > r) return;
    int max_row = tableY.get_max(0,Hr).ss;
    int max_col = tableX.get_max(l,r).ss;
    if(Y[max_row] <= X[max_col])
    {
        rek(l,max_col-1,Hr,pop);
        rek(max_col+1,r,Hr,pop);
        return;
    }
    int min_col = tableX.get_min(l,r).ss;
    int min_row = tableY.get_min(max_row,Hr+1).ss;
    if(X[min_col] >= Y[min_row])
    {
        pop = {max_row,l}; 
    } 
  //  cerr << pop.ff << " " << pop.ss << " " << max_row << " " << min_row << " " << max_col << " " << min_col << " pop\n";
    if(max_row == 0)
    {
      //  cerr << l << " " << r << " xd\n";
        rep2(i,l,r) max_H[i] = pop;
    }
    else
    {
        rek(l,r,max_row-1,pop);
    }
}

void initialize(vi T, vi H) 
{
    T.pb(-1);
    rep(i,siz(T)) Y[i] = T[i];
    rep(i,siz(H)) X[i] = H[i];
    tableY.set(T);
    tableX.set(H);
    rek(0,siz(H)-1,siz(T)-2,{siz(T)-1,0});
}

bool can_reach(int L, int R, int S, int D) 
{
    int row = min(max_H[S].ff,max_H[D].ff);
    int l = max_H[S].ss;
    int r = max_H[D].ss;
  //  cerr << row << " " << l << " " << r << " " << max_H[S].ff << " " << max_H[D].ff << " lr\n";
    if(D > S) swap(D,S);
    return tableX.get_max(D,S).ff < Y[row];
}

• Subtask 0: 0 / 0
• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 13 / 13
• Subtask 4: 0 / 21
• Subtask 5: 0 / 25
• Subtask 6: 0 / 17