Submission #1066040

#	Time	Username	Problem	Language	Result	Execution time	Memory
1066040		j_vdd16	Catfish Farm (IOI22_fish)	C++17	40 / 100	1074 ms	133164 KiB

fish

#include "fish.h"

#include <algorithm>
#include <bitset>
#include <cstdint>
#include <cstring>
#include <iostream>
#include <limits.h>
#include <math.h>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

#define int long long
#define loop(X, N) for(int X = 0; X < (N); X++)
#define all(V) V.begin(), V.end()
#define rall(V) V.rbegin(), V.rend()

using namespace std;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef vector<vector<ii>> vvii;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;

vvii fishes;
vector<map<int, int>> prefixWeight;

int weightSum(int x, int y1, int y2) {
    if (x >= fishes.size() || y2 <= y1)
        return 0;

    // int res = 0;
    // for (auto [y, w] : fishes[x]) {
    //     if (y1 <= y && y < y2)
    //         res += w;
    // }

    // return res;

    auto it1 = prefixWeight[x].upper_bound(y2 - 1);
    auto it2 = prefixWeight[x].upper_bound(y1 - 1);
    int res = (--it1)->second - (--it2)->second;
    //cout << x << ' ' << y1 << ' ' << y2 << " = " << res << endl;
    return res;
}

long long max_weights(signed N, signed M, vector<signed> X, std::vector<signed> Y, std::vector<signed> W) {
    fishes = vvii(N);
    loop(i, M) {
        fishes[X[i]].push_back({Y[i], W[i]});
    }
    fishes.push_back({});

    prefixWeight = vector<map<int, int>>(N + 1);
    loop(x, N + 1) {
        sort(all(fishes[x]));

        int total = 0;
        prefixWeight[x][-2] = 0;
        for (auto [y, w] : fishes[x]) {
            total += w;

            prefixWeight[x][y] = total;
        }
    }

    vector<map<int, int>> beforeDp(N);
    vector<map<int, int>> bothDp(N);

    vi maxBefore(N);
    vi maxBoth(N);

    //bestBefore, bestBeforeAndAfter
    loop(x, N) {
        if (x == 0) {
            for (auto [y, w] : fishes[x + 1]) {
                bothDp[0][y + 1] = weightSum(x + 1, 0, y + 1);
                maxBoth[x] = max(maxBoth[x], bothDp[0][y + 1]);
            }
            beforeDp[0][0] = 0;
            maxBefore[0] = 0;

            continue;
        }

        int bestBefore2 = 0;
        int bestBoth3 = 0;
        if (x >= 2) {
            bestBefore2 = maxBefore[x - 2];
        }
        if (x >= 3) {
            bestBoth3 = maxBoth[x - 3];
        }

        for (const auto& [y, w] : fishes.at(x - 1)) {
            int height = y + 1;
            int& both = bothDp[x][height];
            int& before = beforeDp[x][height];

            for (const auto& [prevHeight, prevScore] : beforeDp.at(x - 1)) {
                int prevCur = weightSum(x - 1, prevHeight, height);

                both = max(both, prevScore + prevCur);
                before = max(before, prevScore + prevCur);
            }
            for (auto [prevY, prevScore] : bothDp[x - 1]) {
                if (prevY <= height) 
                    continue;

                int prevCur = -weightSum(x, 0, height);
                both = max(both, prevScore + prevCur);
            }

            int prevWeight = weightSum(x - 1, 0, height);
            both = max(both, bestBefore2 + prevWeight);
            both = max(both, bestBoth3 + prevWeight);

            before = max(before, bestBefore2 + prevWeight);
            before = max(before, bestBoth3 + prevWeight);
            
            maxBefore[x] = max(maxBefore[x], before);
        }
        for (const auto& [y, w] : fishes.at(x + 1)) {
            int height = y + 1;
            int& both = bothDp[x][height];

            for (const auto& [prevHeight, prevScore] : beforeDp.at(x - 1)) {
                int prevCur = weightSum(x - 1, prevHeight, height);

                both = max(both, prevScore + prevCur);
            }
            for (const auto& [prevY, prevScore] : bothDp.at(x - 1)) {
                if (prevY <= height) 
                    continue;

                int prevCur = -weightSum(x, 0, height);
                both = max(both, prevScore + prevCur);
            }

            int prevWeight = weightSum(x - 1, 0, height);
            both = max(both, bestBefore2 + prevWeight);
            both = max(both, bestBoth3 + prevWeight);
        }

        for (auto [height, score] : bothDp[x]) {
            int nextWeight = weightSum(x + 1, 0, height);
            bothDp[x][height] += nextWeight;
            
            maxBoth[x] = max(maxBoth[x], bothDp[x][height]);
        }

        int& both = bothDp[x][0];
        int& before = beforeDp[x][0];

        both = max({both, maxBefore[x - 1], bestBefore2, bestBoth3});
        before = max(before, both);

        maxBefore[x] = max(maxBefore[x], before);
        maxBoth[x] = max(maxBoth[x], both);
    }

    int res = 0;
    loop(x, N) {
        for (auto [y, score] : beforeDp[x]) {
            res = max(res, score);
        }
        for (auto [y, score] : bothDp[x]) {
            res = max(res, score);
        }
    }

    return res;
}

Compilation message (stderr)

fish.cpp: In function 'long long int weightSum(long long int, long long int, long long int)':
fish.cpp:37:11: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<std::pair<long long int, long long int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   37 |     if (x >= fishes.size() || y2 <= y1)
      |         ~~^~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 0 / 6
• Subtask 3: 9 / 9
• Subtask 4: 14 / 14
• Subtask 5: 0 / 21
• Subtask 6: 0 / 17
• Subtask 7: 14 / 14
• Subtask 8: 0 / 16