Submission #627280

#	Time	Username	Problem	Language	Result	Execution time	Memory
627280		typ_ik	Catfish Farm (IOI22_fish)	C++17	12 / 100	109 ms	7268 KiB

fish

#include <bits/stdc++.h>

#define all(x) (x).begin(), (x).end()

using namespace std;

long long max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W) {
    int block1 = 0;
    for (auto c : X) block1 += (c & 1 ^ 1);
    if (block1 == M)
        return accumulate(all(W), 0ll);

    int mx = -1;
    for (auto c : X) mx = max(mx, c);

    if (mx <= 1) {
        vector <long long> col[2];
        for (auto i : {0, 1})
            col[i].resize(N);

        for (int i = 0; i < M; i++)
            col[X[i]][Y[i]] += W[i];

        for (int i = 0; i < 2; i++)
            for (int j = 1; j < N; j++)
                col[i][j] += col[i][j-1];

        if (N == 2)
            return max(col[0][1], col[0][0]);

        long long ans = col[1][N - 1];
        for (int i = 0; i < N; i++)
            ans = max(ans, col[0][i] + (col[1][N - 1] - col[1][i]));

        return ans;
    }

    long long dp[N + 1][2];
    long long val[N + 1];
    for (int i = 0; i <= N; i++) {
        for (int j : {0, 1})
            dp[i][j] = 0;
        val[i] = 0;
    }

    for (int i = 0; i < M; i++)
        X[i]++;
    for (int i = 0; i < M; i++)
        val[X[i]] = W[i];

    dp[0][1] = val[1];

    for (int i = 2; i <= N; i++) {
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]);
        dp[i][1] = max(dp[i - 1][1] - val[i], max(dp[i - 2][0] + val[i - 1], dp[i - 2][1])) + val[i + 1];
    }

    return max(dp[N - 1][0], dp[N - 1][1]);
}

//main() {
//    int N = 10, M = 4;
//    vector <int> X = {0, 5, 7, 4};
//    vector <int> Y = {0, 0, 0, 0};
//    vector <int> W = {10, 5, 3, 6};
//    cout << max_weights(N, M, X, Y, W) << '\n';
//}

Compilation message (stderr)

fish.cpp: In function 'long long int max_weights(int, int, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:9:35: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
    9 |     for (auto c : X) block1 += (c & 1 ^ 1);
      |                                 ~~^~~

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