제출 #642054

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
642054		dykw	Catfish Farm (IOI22_fish)	C++17	100 / 100	139 ms	20420 KiB

fish

#include "fish.h"

#include <bits/stdc++.h>

using i64 = long long;

i64 max_weights(int N, int M, std::vector<int> X, std::vector<int> Y, std::vector<int> W) {
	std::vector<std::vector<int>> pos(N);
    for (int i = 0; i < M; ++i) {
        pos[X[i]].push_back(i);
    }
    for (int i = 0; i < N; ++i) {
        std::sort(pos[i].begin(), pos[i].end(), [&](int lhs, int rhs) {
            return Y[lhs] < Y[rhs];
        });
    }
    auto chmax = [](i64 &x, i64 y) {
        x = std::max(x, y);
    };
    i64 ans = 0;
    std::vector<i64> f(M), g(M), max_f(N), max_g(N);
    for (int i = 0; i < N; ++i) {
        if (i > 0) {
            max_f[i] = max_g[i] = std::max(max_f[i - 1], max_g[i - 1]);
        }
        int len = pos[i].size(), len_1 = i > 0 ? pos[i - 1].size() : 0, p = 0;
        i64 val;
        if (i < N - 1) {
            val = i > 0 ? max_g[i - 1] : 0;
            if (i > 1) {
                chmax(val, max_f[i - 2]);
            }
            for (int j = 0; j < len; ++j) {
                if (j > 0) {
                    f[pos[i][j]] = f[pos[i][j - 1]] + W[pos[i][j]];
                }
                for (; p < len_1 && Y[pos[i - 1][p]] < Y[pos[i][j]]; ++p) {
                    chmax(val, f[pos[i - 1][p]]);
                }
                chmax(f[pos[i][j]], val + W[pos[i][j]]);
                chmax(max_f[i], f[pos[i][j]]);
                chmax(ans, f[pos[i][j]]);
            }
        }
        if (i > 0) {
            p = len_1 - 1, val = i > 1 ? max_f[i - 2] : 0;
            for (int j = len - 1; j >= 0; --j) {
                if (j < len - 1) {
                    g[pos[i][j]] = g[pos[i][j + 1]] + W[pos[i][j]];
                }
                for (; p >= 0 && Y[pos[i - 1][p]] > Y[pos[i][j]]; --p) {
                    chmax(val, g[pos[i - 1][p]]);
                }
                chmax(g[pos[i][j]], val + W[pos[i][j]]);
                chmax(max_g[i], g[pos[i][j]]);
                chmax(ans, g[pos[i][j]]);
            }
        }
    }
    return ans;
}

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