Submission #1005273

#	Time	Username	Problem	Language	Result	Execution time	Memory
1005273		overwatch9	Catfish Farm (IOI22_fish)	C++17	0 / 100	49 ms	52048 KiB

fish

#include "fish.h"
 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
vector <vector <pair <int, ll>>> fish;
vector <vector <ll>> pfx;
int n, m;
const int maxn = 1e5 + 5;
ll dp[maxn][5][5];
bool ready[maxn][5][5];
ll cost(int i, int h1, int h2, int h3) {
    if (i == 1)
        return 0;
    if (max(h1, h3) <= h2 || (int)fish[i-1].size() == 1)
        return 0;
    int mx = max(h1, h3);
    pair <int, ll> tp = {h2+1, 0};
    int it = lower_bound(fish[i-1].begin(), fish[i-1].end(), tp) - fish[i-1].begin();
    tp.first = mx;
    tp.second = 1e18;
    int it2 = upper_bound(fish[i-1].begin(), fish[i-1].end(), tp) - fish[i-1].begin();
    it2--;
    // if (it == it2)
    //     return 0;
    if (it == 0)
        return pfx[i-1][it2];
    return pfx[i-1][it2] - pfx[i-1][it-1];
}
ll solve(int i, int h1, int h2) {
    if (i == n+1) {
        return cost(i, fish[i-2][h1].first, fish[i-1][h2].first, 0);
    }
    if (ready[i][h1][h2])
        return dp[i][h1][h2];
    ll ans = 0;
    if (i-2 >= 0)
        ans = solve(i+1, h2, 0) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, 0);
    else
        ans = solve(i+1, h2, 0) + cost(i, 0, fish[i-1][h2].first, 0);
    int id = 0;
    if (i-1 >= 1) {
        if (!fish[i-1].empty())
            ans = max(ans, solve(i+1, h2, 0) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i-1][0].first));
        if ((int)fish[i-1].size() == 2)
            ans = max(ans, solve(i+1, h2, 1) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i-1][1].first));
    }
    for (auto j : fish[i]) {
        if (!fish[i].empty()) {
            if (i-2 >= 0)
                ans = max(ans, solve(i+1, h2, 0) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i][0].first));
            else
                ans = max(ans, solve(i+1, h2, 0) + cost(i, 0, fish[i-1][h2].first, fish[i][0].first));
        }
        if ((int)fish[i].size() == 2) {
            if (i-2 >= 0)
                ans = max(ans, solve(i+1, h2, 1) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i][1].first));
            else
                ans = max(ans, solve(i+1, h2, 1) + cost(i, 0, fish[i-1][h2].first, fish[i][1].first));
        }
    }
    if (i+1 <= n) {
        if (!fish[i+1].empty()) {
            if (i-2 >= 0)
                ans = max(ans, solve(i+1, h2, 0) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i+1][0].first));
            else
                ans = max(ans, solve(i+1, h2, 0) + cost(i, 0, fish[i-1][h2].first, fish[i+1][0].first));
        }
        if ((int)fish[i+1].size() == 2) {
            if (i-2 >= 0)
                ans = max(ans, solve(i+1, h2, 1) + cost(i, fish[i-2][h1].first, fish[i-1][h2].first, fish[i+1][1].first));
            else
                ans = max(ans, solve(i+1, h2, 1) + cost(i, 0, fish[i-1][h2].first, fish[i+1][1].first));
        }
    }
    ready[i][h1][h2] = true;
    dp[i][h1][h2] = ans;
    return ans;
}
ll max_weights(int N, int M, vector<int> X, vector<int> Y, vector<int> W) {
    n = N;
    m = M;
    fish.resize(N+1);
    pfx.resize(N+1);
    for (int i = 0; i < M; i++) {
        fish[X[i] + 1].push_back({Y[i] + 1, W[i]});
    }
    // dp = vector <vector <ll>> (N+1, vector <ll> (N+1, -1));
    for (int i = 0; i <= N; i++) {
        fish[i].push_back({0, 0});
        sort(fish[i].begin(), fish[i].end());
        pfx[i].resize((int)fish[i].size() + 5, 1e18);
        pfx[i][0] = 0;
        for (int j = 1; j < (int)fish[i].size(); j++)
            pfx[i][j] = pfx[i][j-1] + fish[i][j].second;
    }
    return solve(1, 0, 0);
}
// int main() {
//     int nn, mm;
//     cin >> nn >> mm;
//     vector <int> x(mm), y(mm), w(mm);
//     for (int i = 0; i < mm; i++)
//         cin >> x[i] >> y[i] >> w[i];
//     cout << max_weights(nn, mm, x, y, w) << '\n';
// }

Compilation message (stderr)

fish.cpp: In function 'll solve(int, int, int)':
fish.cpp:48:15: warning: variable 'j' set but not used [-Wunused-but-set-variable]
   48 |     for (auto j : fish[i]) {
      |               ^
fish.cpp:41:9: warning: unused variable 'id' [-Wunused-variable]
   41 |     int id = 0;
      |         ^~

• 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