Submission #764453

# Submission time Handle Problem Language Result Execution time Memory
764453 2023-06-23T12:18:26 Z boris_mihov Dancing Elephants (IOI11_elephants) C++17
50 / 100
9000 ms 10868 KB
#include "elephants.h"
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <random>
#include <vector>
#include <set>

typedef long long llong;
const int MAXNUM = 1000000000;
const int BUCKET_SIZE = 2000;
const int MAXN = 150000 + 10;
const int INF  = 2e9;

int n, len;
int a[MAXN];
int x[MAXN];
std::vector <int> nums[BUCKET_SIZE];
std::vector <std::pair <int,int>> dp[BUCKET_SIZE];

void fix(int idx)
{
    dp[idx].resize(nums[idx].size());
    int ptr = nums[idx].size();

    for (int i = (int)nums[idx].size() - 1 ; i >= 0 ; --i)
    {
        while (ptr > 0 && nums[idx][i] + len < nums[idx][ptr - 1])
        {
            ptr--;
        }

        if (ptr == nums[idx].size())
        {
            dp[idx][i] = {1, nums[idx][i] + len};
        } else
        {
            dp[idx][i] = dp[idx][ptr];
            dp[idx][i].first++;
        }
    }
}

void erase(int idx, int val)
{
    for (int i = 0 ; i < nums[idx].size() ; ++i)
    {
        if (nums[idx][i] == val)
        {
            nums[idx].erase(nums[idx].begin() + i);
            break;
        }
    }

    fix(idx);
}

void insert(int idx, int val)
{
    bool inserted = false;
    for (int i = 0 ; i < nums[idx].size() ; ++i)
    {   
        if (val < nums[idx][i])
        {
            nums[idx].insert(nums[idx].begin() + i, val);
            inserted = true;
            break;
        }
    }   

    if (!inserted)
    {
        nums[idx].push_back(val);
    }

    fix(idx);
}

std::multiset <int> ms;
void init(int N, int L, int X[])
{
    n = N;
    len = L;

    for (int i = 1 ; i <= n ; ++i)
    {
        x[i] = a[i] = X[i - 1];
    }

    for (int i = 1 ; i <= n ; ++i)
    {
        nums[i / BUCKET_SIZE].push_back(a[i]);
    }

    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {
        std::sort(nums[i].begin(), nums[i].end());
        fix(i);
    }
}

void rebuild()
{
    for (int i = 1 ; i <= n ; ++i)
    {
        a[i] = x[i];
    }

    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {   
        nums[i].clear();
    }

    std::sort(a + 1, a + 1 + n);
    for (int i = 1 ; i <= n ; ++i)
    {
        nums[i / BUCKET_SIZE].push_back(a[i]);
    }

    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {
        std::sort(nums[i].begin(), nums[i].end());
        fix(i);
    }
}

int update(int idx, int y)
{
    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {
        if (nums[i].size() > n / 4)
        {
            rebuild();
            break;
        }
    }

    idx++;
    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {
        if (nums[i].empty())
        {
            continue;
        }

        if (nums[i][0] <= x[idx] && x[idx] <= nums[i].back())
        {
            erase(i, x[idx]);
            break;
        }
    }

    x[idx] = y;
    bool inserted = false;
    int lastBucket = -1;

    for (int i = 0 ; i < BUCKET_SIZE ; ++i)
    {
        if (nums[i].empty())
        {
            continue;
        }

        lastBucket = i;
        if (nums[i][0] <= x[idx] && x[idx] <= nums[i].back())
        {
            inserted = true;
            insert(i, x[idx]);
            break;
        }

        if (nums[i][0] > x[idx])
        {
            inserted = true;
            insert(i, x[idx]);
        }
    }

    if (!inserted)
    {
        insert(lastBucket, x[idx]);
    }

    int res = 0;
    int coveredTo = -1;
    for (int bucket = 0 ; bucket <= 100 ; ++bucket)
    {
        if (nums[bucket].empty())
        {
            continue;
        }

        if (coveredTo >= nums[bucket].back())
        {
            continue;
        }
        
        int l = -1, r = nums[bucket].size() - 1, mid;
        while (l < r - 1)
        {
            mid = (l + r) / 2;
            if (nums[bucket][mid] <= coveredTo) l = mid;
            else r = mid;
        }

        res += dp[bucket][r].first;
        coveredTo = dp[bucket][r].second;
    }

    return res;
}

Compilation message

elephants.cpp: In function 'void fix(int)':
elephants.cpp:34:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |         if (ptr == nums[idx].size())
      |             ~~~~^~~~~~~~~~~~~~~~~~~
elephants.cpp: In function 'void erase(int, int)':
elephants.cpp:47:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |     for (int i = 0 ; i < nums[idx].size() ; ++i)
      |                      ~~^~~~~~~~~~~~~~~~~~
elephants.cpp: In function 'void insert(int, int)':
elephants.cpp:62:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for (int i = 0 ; i < nums[idx].size() ; ++i)
      |                      ~~^~~~~~~~~~~~~~~~~~
elephants.cpp: In function 'int update(int, int)':
elephants.cpp:132:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  132 |         if (nums[i].size() > n / 4)
      |             ~~~~~~~~~~~~~~~^~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 2 ms 340 KB Output is correct
5 Correct 2 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 2 ms 340 KB Output is correct
5 Correct 2 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1369 ms 1612 KB Output is correct
8 Correct 1943 ms 1968 KB Output is correct
9 Correct 581 ms 2464 KB Output is correct
10 Correct 963 ms 2464 KB Output is correct
11 Correct 983 ms 2460 KB Output is correct
12 Correct 1431 ms 2764 KB Output is correct
13 Correct 1037 ms 2460 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 2 ms 340 KB Output is correct
5 Correct 2 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1369 ms 1612 KB Output is correct
8 Correct 1943 ms 1968 KB Output is correct
9 Correct 581 ms 2464 KB Output is correct
10 Correct 963 ms 2464 KB Output is correct
11 Correct 983 ms 2460 KB Output is correct
12 Correct 1431 ms 2764 KB Output is correct
13 Correct 1037 ms 2460 KB Output is correct
14 Correct 893 ms 2144 KB Output is correct
15 Correct 913 ms 1868 KB Output is correct
16 Correct 2308 ms 2840 KB Output is correct
17 Correct 2574 ms 3724 KB Output is correct
18 Correct 2920 ms 3664 KB Output is correct
19 Execution timed out 9024 ms 10868 KB Time limit exceeded
20 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 2 ms 340 KB Output is correct
5 Correct 2 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1369 ms 1612 KB Output is correct
8 Correct 1943 ms 1968 KB Output is correct
9 Correct 581 ms 2464 KB Output is correct
10 Correct 963 ms 2464 KB Output is correct
11 Correct 983 ms 2460 KB Output is correct
12 Correct 1431 ms 2764 KB Output is correct
13 Correct 1037 ms 2460 KB Output is correct
14 Correct 893 ms 2144 KB Output is correct
15 Correct 913 ms 1868 KB Output is correct
16 Correct 2308 ms 2840 KB Output is correct
17 Correct 2574 ms 3724 KB Output is correct
18 Correct 2920 ms 3664 KB Output is correct
19 Execution timed out 9024 ms 10868 KB Time limit exceeded
20 Halted 0 ms 0 KB -