Submission #701470

# Submission time Handle Problem Language Result Execution time Memory
701470 2023-02-21T10:13:09 Z boris_mihov Catfish Farm (IOI22_fish) C++17
0 / 100
37 ms 22840 KB
#include "fish.h"
#include <algorithm>
#include <iostream>
#include <cassert>
#include <numeric>
#include <vector>

typedef long long llong;
const int MAXN = 100000 + 10;
const int MAXM = 600000 + 10;

struct Position
{
    int y;
    int idx;
    llong in;
    llong left;
    llong right;

    Position(int _y, int _idx, llong _left, llong _right)
    {
        y = _y;
        idx = _idx;
        left = _left;
        right = _right;
    }
};

int cnt;
struct SegmentTree
{
    llong tree[4*MAXM];
    void update(int l, int r, int node, int queryIdx, llong value)
    {
        if (l == r)
        {
            tree[node] = value;
            return;
        }

        int mid = (l + r) / 2;
        if (queryIdx <= mid) update(l, mid, 2*node, queryIdx, value);
        else update(mid + 1, r, 2*node + 1, queryIdx, value);
        tree[node] = std::max(tree[2*node], tree[2*node + 1]);
    }

    llong query(int l, int r, int node, int queryL, int queryR)
    {
        if (queryL <= l && r <= queryR)
        {
            return tree[node];
        }

        llong ans = -1e18;
        int mid = (l + r) / 2;
        if (queryL <= mid) ans = std::max(ans, query(l, mid, 2*node, queryL, queryR));
        if (mid + 1 <= queryR) ans = std::max(ans, query(mid + 1, r, 2*node + 1, queryL, queryR));
        return ans; 
    }

    void update(int pos, llong value)
    {
        update(1, cnt, 1, pos, value);
    }

    llong query(int l, int r)
    {
        return query(1, cnt, 1, l, r);
    }
};

int n, m;
llong dp[MAXM];
std::vector <Position> pos[MAXN];
std::vector <Position> posUncleared[MAXN];
std::vector <std::pair <int,int>> fish[MAXN];
SegmentTree LR, minusL, minusIN;

llong max_weights(int N, int M, std::vector<int> X, std::vector<int> Y, std::vector<int> W) 
{
    n = N; m = M;   
    for (int i = 0 ; i < m ; ++i)
    {
        fish[X[i] + 1].emplace_back(Y[i] + 1, W[i]);
    }

    for (int x = 1 ; x <= n ; ++x)
    {
        for (const auto &[y, w] : fish[x])
        {
            if (x != 1)
            {
                assert(y != 1);
                posUncleared[x - 1].push_back({y, 0, 0LL, 0LL});
            }

            if (x != n)
            {
                assert(y != 1);
                posUncleared[x + 1].push_back({y, 0, 0LL, 0LL});
            }
        }
    }

    return 0;
    for (int x = 1 ; x <= n ; ++x)
    {
        std::sort(posUncleared[x].begin(), posUncleared[x].end(), [&](Position a, Position b)
        {
            return a.y < b.y;
        });

        for (Position p : posUncleared[x])
        {
            if (!pos[x].empty() && pos[x].back().y == p.y)
            {
                continue;
            }

            p.idx = ++cnt;
            pos[x].push_back(p);
        }

        int ptrL = 0;
        int ptrR = 0;
        int ptrIN = 0;
        llong inSum = 0;
        llong leftSum = 0;
        llong rightSum = 0;
        for (Position &p : pos[x])
        {
            while (ptrL < fish[x - 1].size() && fish[x - 1][ptrL].first <= p.y)
            {
                leftSum += fish[x - 1][ptrL].second;
                ptrL++;
            }

            while (ptrR < fish[x + 1].size() && fish[x + 1][ptrR].first <= p.y)
            {
                rightSum += fish[x + 1][ptrR].second;
                ptrR++;
            }

            while (ptrIN < fish[x].size() && fish[x][ptrIN].first <= p.y)
            {
                inSum += fish[x][ptrIN].second;
                ptrIN++;
            }

            p.in = inSum;
            p.left = leftSum;
            p.right = rightSum;
        }
    }

    for (int x = n ; x >= 1 ; --x)
    {
        for (const Position &curr : pos[x])
        {
            if (x == n)
            {
                LR.update(curr.idx, dp[curr.idx] + curr.left + curr.right);
                minusL.update(curr.idx, dp[curr.idx] - curr.left + curr.right);
                minusIN.update(curr.idx, dp[curr.idx] - curr.in + curr.right);
                continue;
            }

            int l = -1, r = pos[x + 1].size(), mid;
            while (l < r - 1)
            {
                mid = (l + r) / 2;
                if (pos[x + 1][mid].y < curr.y) l = mid;
                else r = mid;
            }

            if (l >= 0)
            {
                dp[curr.idx] = std::max(dp[curr.idx], minusIN.query(pos[x + 1][0].idx, pos[x + 1][l].idx));
            }

            if (r < pos[x + 1].size())
            {
                dp[curr.idx] = std::max(dp[curr.idx], LR.query(pos[x + 1][r].idx, pos[x + 1].back().idx) - curr.in - curr.right);
            }

            if (x + 2 <= n)
            {
                l = -1;
                r = pos[x + 2].size();
                while (l < r - 1)
                {
                    mid = (l + r) / 2;
                    if (pos[x + 2][mid].y < curr.y) l = mid;
                    else r = mid;
                }

                if (l >= 0)
                {
                    dp[curr.idx] = std::max(dp[curr.idx], minusL.query(pos[x + 2][0].idx, pos[x + 2][l].idx));
                }

                if (r < pos[x + 2].size())
                {
                    dp[curr.idx] = std::max(dp[curr.idx], LR.query(pos[x + 2][r].idx, pos[x + 2].back().idx) - curr.right);
                }
            }

            int firstIdx = pos[x].back().idx + 1;
            if (!pos[x + 1].empty())
            {
                firstIdx = pos[x + 1].back().idx + 1;
            }

            if (!pos[x + 2].empty())
            {
                firstIdx = pos[x + 2].back().idx + 1;
            }

            if (firstIdx <= cnt)
            {
                dp[curr.idx] = std::max(dp[curr.idx], LR.query(firstIdx, cnt));
            }

            LR.update(curr.idx, dp[curr.idx] + curr.left + curr.right);
            minusL.update(curr.idx, dp[curr.idx] - curr.left + curr.right);
            minusIN.update(curr.idx, dp[curr.idx] - curr.in + curr.right);
        }
    }

    return LR.query(1, cnt);
}

Compilation message

fish.cpp: In function 'llong max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:132:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  132 |             while (ptrL < fish[x - 1].size() && fish[x - 1][ptrL].first <= p.y)
      |                    ~~~~~^~~~~~~~~~~~~~~~~~~~
fish.cpp:138:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  138 |             while (ptrR < fish[x + 1].size() && fish[x + 1][ptrR].first <= p.y)
      |                    ~~~~~^~~~~~~~~~~~~~~~~~~~
fish.cpp:144:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  144 |             while (ptrIN < fish[x].size() && fish[x][ptrIN].first <= p.y)
      |                    ~~~~~~^~~~~~~~~~~~~~~~
fish.cpp:181:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Position>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  181 |             if (r < pos[x + 1].size())
      |                 ~~^~~~~~~~~~~~~~~~~~~
fish.cpp:202:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Position>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  202 |                 if (r < pos[x + 2].size())
      |                     ~~^~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Runtime error 37 ms 22840 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14712 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14676 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14676 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14676 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14676 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 14676 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 37 ms 22840 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -