Submission #1234713

#	Time	Username	Problem	Language	Result	Execution time	Memory
1234713		trimkus	Catfish Farm (IOI22_fish)	C++20	100 / 100	237 ms	74896 KiB

fish

#include "fish.h"

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

void chmax(ll& x, ll y) {
  x = max(x, y);
}

long long max_weights(int N, int M, std::vector<int> X, std::vector<int> Y,
                      std::vector<int> W) {
    vector<vector<array<ll, 2>>> a(N + 3);
    for (int i = 0; i < M; ++i) {
      a[X[i] + 1].push_back({Y[i] + 1, W[i]});
    }
    for (int i = 1; i < N; ++i) {
      a[i].push_back({0, 0});
      a[i].push_back({N + 1, 0});
      for (auto& u : a[i + 1]) {
          a[i].push_back({u[0], 0});
      }
    }
    for (int i = N; i > 1; --i) {
      a[i].push_back({0, 0});
      a[i].push_back({N + 1, 0});
      for (auto& u : a[i - 1]) {
        a[i].push_back({u[0], 0});
      }
    }
    for (int i = 1; i <= N; ++i) {
        sort(begin(a[i]), end(a[i]));
        vector<array<ll, 2>> unq{a[i][0]};
        for (int j = 1; j < (int)a[i].size(); ++j) {
          if (unq.back()[0] != a[i][j][0]) {
            unq.push_back(a[i][j]);
          } else {
            unq.back()[1] = a[i][j][1];
          }
        }
        a[i] = unq;
    }
    // for (int i = 1; i <= N; ++i) {
    //   for (auto& [x, w] : a[i]) {
    //     cout << x << " " << w << "\n";
    //   }
    //   cout << "\n";
    // }
    vector<vector<array<ll, 2>>> dp(N + 2);
    for (int i = 1; i <= N; ++i) {
      dp[i].resize(a[i].size() + 1);
    }
    // 1 - for hi <= h(i - 1)
    // 0 - for hi >= h(i - 1)
    for (int i = 2; i <= N; ++i) {
        // cerr << i << "\n";
      ll res = 0;
      int ptr = a[i - 1].size() - 1;
      for (int j = (int)a[i].size() - 1; j >= 0; --j) {
          while (ptr >= 0 && a[i - 1][ptr][0] >= a[i][j][0]) {
              res = max({res, dp[i - 1][ptr][0], dp[i - 1][ptr][1]});
              ptr -= 1;
          }
          dp[i][j][1] = max(dp[i][j][1], res);
          res += a[i][j][1];
      }
      res = 0;
      ptr = 0;
      for (int j = 0; j < (int)a[i].size(); ++j) {
        while (ptr < (int)a[i - 1].size() && a[i - 1][ptr][0] <= a[i][j][0]) {
          res = max(res, dp[i - 1][ptr][1]);
          ptr += 1;
        }
        dp[i][j][0] = max(res, dp[i][j][0]);
      }
      res = 0;
      ptr = 0;
      for (int j = 0; j < (int)a[i].size(); ++j) {
        while (ptr < (int)a[i - 1].size() && a[i - 1][ptr][0] <= a[i][j][0]) {
            res = max(res + a[i - 1][ptr][1], dp[i - 1][ptr][0]);
            ptr += 1;
        }
        dp[i][j][0] = max(dp[i][j][0], res);
      }

    }
    // for (int i = 1; i <= N; ++i) {
    //   for (int j = 0; j < (int)a[i].size(); ++j) {
    //       cerr << a[i][j][0] << " = ";
    //     for (int k = 0; k < 2; ++k) {
    //       cerr << dp[i][j][k] << " ";
    //     }
    //     cerr << "\n";
    //   }
    //   cerr << "\n";
    // }
    // cerr << "\n";
    ll res = 0;
    for (int i = 0; i < (int)a[N].size(); ++i) {
      for (int k = 0; k < 2; ++k) {
        res = max(res, dp[N][i][k]);
      }
    }
    // cerr << res << "\n";
    return res;
}

• 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