Submission #914878

#	Time	Username	Problem	Language	Result	Execution time	Memory
914878		davitmarg	Towers (NOI22_towers)	C++17	18 / 100	1173 ms	180608 KiB

Main

/*
DavitMarg
In a honky-tonk,
Down in Mexico
*/
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <string>
#include <cstring>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <queue>
#include <bitset>
#include <stack>
#include <cassert>
#include <iterator>
#include <random>
#include <chrono>
#define mod 998244353ll
#define LL long long
#define LD long double
#define MP make_pair    
#define PB push_back
#define all(v) v.begin(), v.end()
#define fastIO ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
using namespace std;

const int N = 1000006;

#define X first.first
#define Y first.second
#define I second
#define pt pair<pair<int,int>, int>

int n, k;
int ans[N];
pt p[N];
vector<pt> x[N], y[N];
int used_x[N];
vector<int> last_x[N];
int ly[N], ry[N];

void lesgo(int i, pt a)
{
    int pos;
    if (used_x[a.X] > 2)
    {
        used_x[a.X]--;
        int last_y = last_x[a.X].back();
        if (y[last_y][ly[last_y]].X == y[last_y][ry[last_y]].X)
        {
            last_x[y[last_y][ly[last_y]].X].pop_back();
            ly[last_y]++;
        }
        else if (y[last_y][ly[last_y]].X == a.X)
        {
            pos = ly[last_y];
            last_x[y[last_y][pos].X].pop_back();
            pos++;
			ly[last_y] = pos;
            if (pos < ry[last_y])
            {
				used_x[y[last_y][pos].X]++;
				lesgo(last_y, y[last_y][pos]);
                last_x[y[last_y][pos].X].push_back(last_y);
			}
        }
        else
        {
            pos = ry[last_y];
            last_x[y[last_y][pos].X].pop_back();
            pos--;
            ry[last_y] = pos;
            if (pos > ly[last_y])
            {
                used_x[y[last_y][pos].X]++;
				lesgo(last_y, y[last_y][pos]);
                last_x[y[last_y][pos].X].push_back(last_y);
            }
        }
    }
}

void solve()
{
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        cin >> p[i].X >> p[i].Y;
        k = max(k, max(p[i].X, p[i].Y));
        p[i].I = i;
        y[p[i].Y].PB(p[i]);
        x[p[i].X].PB(p[i]);
    }

    for (int i = 1; i <= k; i++)
    {
        sort(all(x[i]), [](pt a, pt b) {return a.Y < b.Y; });
        sort(all(y[i]), [](pt a, pt b) {return a.X < b.X; });
    }

    for (int i = 1; i <= k; i++)
    {
       if(y[i].empty())
           continue;

       used_x[y[i][0].X]++;
       ly[i] = 0;
       lesgo(i, y[i][0]);
       last_x[y[i][0].X].push_back(i);


       ry[i] = y[i].size() - 1;
       if(y[i].size() != 1)
           used_x[y[i].back().X]++;

       lesgo(i, y[i].back());
       if (y[i].size() != 1)
          last_x[y[i].back().X].push_back(i);
    }


    for (int i = 1; i <= k; i++)
    {
        if(y[i].empty())
            continue;
        if(ly[i] <= ry[i])
            ans[y[i][ly[i]].I] = ans[y[i][ry[i]].I] = 1;
    }

    for (int i = 1; i <= n; i++)
        cout << ans[i];
    cout << endl;

}


int main()
{
    fastIO;
    int T = 1;
    //cin >> T;
    while (T--)
    {
        solve();
    }

    return 0;
}

/*

8
1 1
2 1
3 1
1 2
2 2
3 2
2 3
3 3


20
1 1
2 1
3 1
4 1
1 2
2 2
3 2
4 2
1 3
2 3
3 3
4 3
1 4
2 4
3 4
4 4
1 5
2 5
3 5
4 5

 
3
1 1
1 6
1 5


*/

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 7 / 7
• Subtask 4: 6 / 6
• Subtask 5: 0 / 31
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19