제출 #654092

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
654092		noedit	코끼리 (Dancing Elephants) (IOI11_elephants)	C++17	100 / 100	6071 ms	11844 KiB

elephants

#include "elephants.h"
#include <bits/stdc++.h>

using namespace std;

const int INF = 2e9;
const int MAXN = 1e5 + 5e4;
const int B = 350;

int n, l, q = 0;

int x[MAXN + 1];

int bid[MAXN + 1];

int go[MAXN + 1];

int cnt[MAXN + 1];

int ord[MAXN + 1];

vector<vector<int> > bs;



void build_block(int num)
{
    int pt = bs[num].size() - 1;
    for (int i = bs[num].size() - 1; i >= 0; i--)
    {
        if (x[bs[num][i]] + l >= x[bs[num].back()])
        {
            go[bs[num][i]] = x[bs[num][i]] + l;
            cnt[bs[num][i]] = 1;
        }
        else
        {
            while (x[bs[num][i]] + l < x[bs[num][pt]])
                pt--;
            go[bs[num][i]] = go[bs[num][pt + 1]];
            cnt[bs[num][i]] = cnt[bs[num][pt + 1]] + 1;
        }
    }
}

void build()
{
    bs.clear();
    fill(go, go + n + 1, -1);
    fill(cnt, cnt + n + 1, 1);
    bs.resize(n / B + 1);
    sort(ord, ord + n, [&](int a, int b){return x[a] < x[b];});
    for (int i = 0; i < n; i++)
    {
        bs[i / B].push_back(ord[i]);
        bid[ord[i]] = i / B;
    }
    for (int i = 0; i < n / B + 1; i++)
    {
        build_block(i);
    }
}

int calc()
{
    int cur = -1;
    int ans = 0;
    for (int i = 0; i < bs.size(); i++)
    {
        if (bs[i].empty())
            continue;
        auto it = upper_bound(bs[i].begin(), bs[i].end(), cur, [&](int val, int elem) {return val < x[elem];});
        if (it == bs[i].end())
        {
            continue;
        }
        ans += cnt[*it];
        cur = go[*it];
    }
    return ans;
}

void init(int N, int L, int X[])
{
    n = N;
    l = L;
    for (int i = 0; i < n; i++)
    {
        x[i] = X[i];
        ord[i] = i;
    }
    build();
}

int update(int i, int y)
{
    q++;
    if (q == 2 * B)
    {
        x[i] = y;
        build();
        q = 0;
    }
    else
    {
        int pt = 0;
        for (int j = 0; j < bs[bid[i]].size(); j++)
        {
            if (bs[bid[i]][j] == i)
            {
                pt = j;
                break;
            }
        }
        bs[bid[i]].erase(bs[bid[i]].begin() + pt);
        build_block(bid[i]);
        pt = 0;
//        if (y <= x[i])
//        {
//            for (int j = 0; j <= bid[i]; j++)
//            {
//                if (bs[j].empty())
//                    continue;
//                if (x[bs[j][0]] <= y)
//                {
//                    pt = j;
//                }
//            }
//        }
//        else
//        {
            for (int j = 0; j < bs.size(); j++)
            {
                if (bs[j].empty())
                    continue;
                if (x[bs[j][0]] <= y)
                {
                    pt = j;
                }
            }
        //}
        x[i] = y;
        bid[i] = pt;
        pt = bs[bid[i]].size();
        for (int j = 0; j < bs[bid[i]].size(); j++)
        {
            if (x[bs[bid[i]][j]] >= x[i])
            {
                pt = j;
                break;
            }
        }
        bs[bid[i]].insert(bs[bid[i]].begin() + pt, i);
        build_block(bid[i]);
    }
//    for (int i = 0; i < bs.size(); i++)
//    {
//        cout << i << " block: \n";
//        for (auto& j : bs[i])
//            cout << j << " " << x[j] << endl;
//    }
    return calc();
}

컴파일 시 표준 에러 (stderr) 메시지

elephants.cpp: In function 'int calc()':
elephants.cpp:68:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |     for (int i = 0; i < bs.size(); i++)
      |                     ~~^~~~~~~~~~~
elephants.cpp: In function 'int update(int, int)':
elephants.cpp:107:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |         for (int j = 0; j < bs[bid[i]].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~~~~~
elephants.cpp:132:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  132 |             for (int j = 0; j < bs.size(); j++)
      |                             ~~^~~~~~~~~~~
elephants.cpp:145:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  145 |         for (int j = 0; j < bs[bid[i]].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 24 / 24
• Subtask 4: 47 / 47
• Subtask 5: 3 / 3