Submission #656326

#	Time	Username	Problem	Language	Result	Execution time	Memory
656326		Lobo	Catfish Farm (IOI22_fish)	C++17	37 / 100	1099 ms	129392 KiB

fish

#include "fish.h"
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define mp make_pair
#define fr first
#define sc second
#define all(x) x.begin(),x.end()

const int maxn = 1e5+10;
const int maxqh = 12;
const int inf = 1e18+10;

int n, m;
vector<vector<int>> dp[maxn];
map<int,int> pf[maxn];
vector<pair<int,int>> fish[maxn]; // fishs from column i
vector<int> hr[maxn]; // important heights from column i, the ones that can be chosen

long long max_weights(int32_t N, int32_t M, vector<int32_t> X, vector<int32_t> Y, vector<int32_t> W) {
    n = N;
    m = M;

    for(int i = 0; i < m; i++) {
        fish[X[i]+1].pb(mp(Y[i]+1,W[i]));
        hr[X[i]+1].pb(Y[i]);
    }

    for(int i = 0; i <= n; i++) {
        hr[i].pb(0);
        hr[i].pb(n);
        sort(all(hr[i]));
        sort(all(fish[i]));
        hr[i].erase(unique(all(hr[i])),hr[i].end());
        // Store only the relevant heights

        for(int j = 0; j < hr[i].size(); j++) {
            dp[i].pb({0,0});
        }
    }

    for(int i = 1; i <= n; i++) {
        for(auto j : hr[i-1]) pf[i][j] = 0;
        for(auto j : hr[i]) pf[i][j] = 0;
        for(auto j : hr[i+1]) pf[i][j] = 0;

        for(auto aux : fish[i]) {
            int y = aux.fr;
            int w = aux.sc;
            pf[i][y]+= w;
        }
        // Do a prefix sum on the weight of the fishs
        pf[i][0] = 0;
        for(auto it = next(pf[i].begin()); it != pf[i].end(); it++) {
            it->sc+= prev(it)->sc;
        }
    }

    // dp[i][h0][0/1] = until i, with h[i] = hr[i][h0] 
    // and it's greater/smaller tha the previous

    // dp[1][h0][0/1] = 0
    for(int i = 0; i < hr[1].size(); i++) {
        dp[1][i][0] = 0;
        dp[1][i][1] = 0;
    }

    for(int i = 2; i <= n; i++) {
        for(int h0 = 0; h0 < hr[i].size(); h0++) {
            // It's greater than the previous
            dp[i][h0][0] = 0;
            for(int h1 = 0; h1 < hr[i-1].size(); h1++) {
                if(hr[i-1][h1] > hr[i][h0]) continue;
                dp[i][h0][0] = max(dp[i][h0][0], dp[i-1][h1][0] + pf[i-1][hr[i][h0]]-pf[i-1][hr[i-1][h1]]);
            }

            if(i != 2) {
                for(int h2 = 0; h2 < hr[i-2].size(); h2++) {
                    dp[i][h0][0] = max(dp[i][h0][0], dp[i-2][h2][1] + pf[i-1][max(hr[i][h0],hr[i-2][h2])]);
                    dp[i][h0][0] = max(dp[i][h0][0], dp[i-2][h2][0] + pf[i-1][max(hr[i][h0],hr[i-2][h2])]);
                }
            }

            // It's smaller than the previous
            dp[i][h0][1] = 0;
            for(int h1 = 0; h1 < hr[i-1].size(); h1++) {
                if(hr[i-1][h1] < hr[i][h0]) continue;
                dp[i][h0][1] = max(dp[i][h0][1], dp[i-1][h1][0] + pf[i][hr[i-1][h1]] - pf[i][hr[i][h0]]);
                dp[i][h0][1] = max(dp[i][h0][1], dp[i-1][h1][1] + pf[i][hr[i-1][h1]] - pf[i][hr[i][h0]]);
            }
        }
    }

    // cout << dp[2][hr[4].size()-1][1] << endl;

    int ans = 0;
    for(int h0 = 0; h0 < hr[n].size(); h0++) {
        ans = max(ans, dp[n][h0][0]);
        ans = max(ans, dp[n][h0][1]);
    }
    return ans;
}

Compilation message (stderr)

fish.cpp: In function 'long long int max_weights(int32_t, int32_t, std::vector<int>, std::vector<int>, std::vector<int>)':
fish.cpp:38:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         for(int j = 0; j < hr[i].size(); j++) {
      |                        ~~^~~~~~~~~~~~~~
fish.cpp:64:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |     for(int i = 0; i < hr[1].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~
fish.cpp:70:28: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |         for(int h0 = 0; h0 < hr[i].size(); h0++) {
      |                         ~~~^~~~~~~~~~~~~~
fish.cpp:73:32: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   73 |             for(int h1 = 0; h1 < hr[i-1].size(); h1++) {
      |                             ~~~^~~~~~~~~~~~~~~~
fish.cpp:79:36: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |                 for(int h2 = 0; h2 < hr[i-2].size(); h2++) {
      |                                 ~~~^~~~~~~~~~~~~~~~
fish.cpp:87:32: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |             for(int h1 = 0; h1 < hr[i-1].size(); h1++) {
      |                             ~~~^~~~~~~~~~~~~~~~
fish.cpp:98:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   98 |     for(int h0 = 0; h0 < hr[n].size(); h0++) {
      |                     ~~~^~~~~~~~~~~~~~

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