Submission #1261118

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261118		rayan_bd	Catfish Farm (IOI22_fish)	C++20	0 / 100	1099 ms	138912 KiB

fish

#include "fish.h"
#include <bits/stdc++.h>
using namespace std;
const int MAX = 3010;
long long dp[MAX][MAX][3];
long long pref[MAX][MAX], mat[MAX][MAX];

long long max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W) {
    // Build weight matrix
    for (int i = 0; i < M; i++) {
        mat[X[i]+1][Y[i]+1] += W[i];
    }

    // Build prefix sums for each column
    for (int i = 1; i <= N; i++) {
        for (int j = 1; j <= N; j++) {
            pref[i][j] = pref[i][j-1] + mat[i][j];
        }
    }

    // Initialize
    for (int j = 1; j <= N; j++) {
        dp[1][j][1] = pref[1][j];
        dp[1][j][2] = dp[1][j][1];
    }

    // Transition
    for (int i = 2; i <= N; i++) {
        long long bestPrev = 0;
        for (int k = 0; k <= N; k++)
            bestPrev = max({bestPrev, dp[i-1][k][0], dp[i-1][k][1], dp[i-1][k][2]});

        for (int j = 1; j <= N; j++) {
            // state 0: block
            dp[i][j][0] = bestPrev;

            // state 1: take bottom j
            dp[i][j][1] = max(dp[i][j-1][1], bestPrev + pref[i][j]);

            // state 2: merge with previous column
            dp[i][j][2] = max(dp[i][j-1][2], dp[i-1][j][1] + pref[i][j]);
        }
    }

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

    return ans;
}

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