Submission #661160

#	Time	Username	Problem	Language	Result	Execution time	Memory
661160		mychecksedad	Catfish Farm (IOI22_fish)	C++17	100 / 100	306 ms	57308 KiB

fish

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define pb push_back
const int N = 1e5 + 100;


long long max_weights(int n, int m, vector<int> x, vector<int> y, vector<int> w){  
    vector<ll> fishes[N];
    vector<vector<int>> states(n + 1, {0});
    for(int i = 0; i < m; ++i){
        ++y[i];
        for(int k = max(0, x[i] - 1); k <= min(n - 1, x[i] + 1); ++k){
            states[k].pb(y[i]);
        }
    }
    for(int i = 0; i <= n; ++i){
        sort(states[i].begin(), states[i].end());
        states[i].erase(unique(states[i].begin(), states[i].end()), states[i].end());
        fishes[i].resize(states[i].size());
    }
    for(int i = 0; i < m; ++i){
        int j = x[i];
        int Y = lower_bound(states[j].begin(), states[j].end(), y[i]) - states[j].begin();
        fishes[j][Y] += w[i];
    }
    vector<vector<ll>> dp_up(n + 1), dp_down(n + 1);

    for(int i = 0; i <= n; ++i){
        int sz = states[i].size();
        dp_up[i].resize(sz, 0);
        dp_down[i].resize(sz, 0);
        if(i > 0){
            ll best = dp_down[i - 1][0], sum = 0;
            for(int j = 0, left = 0; j < sz; ++j){
                while(left + 1 < states[i - 1].size() && states[i - 1][left + 1] <= states[i][j]){
                    ++left;
                    best += fishes[i - 1][left];
                    best = max(best, dp_down[i - 1][left]);
                }
                dp_down[i][j] = max(dp_down[i][j], best);
            }
            best = 0;
            sum = accumulate(fishes[i].begin(), fishes[i].end(), 0ll);
            for(int j = sz - 1, left = states[i - 1].size(); j >= 0; --j){
                while(left > 0 && states[i - 1][left - 1] >= states[i][j]){
                    --left;
                    best = max(best, max(dp_up[i - 1][left], dp_down[i - 1][left]) + sum);
                }
                dp_up[i][j] = max(dp_up[i][j], best - sum);
                sum -= fishes[i][j];
            }
        }
        if(i > 1){
            ll best = max(dp_down[i - 2][0], dp_up[i - 2][0]), sum = 0;
            for(int j = 0, left = 0, leftt = 0; j < sz; ++j){
                while(leftt + 1 < states[i - 2].size() && states[i - 2][leftt + 1] <= states[i][j]){
                    ++leftt;
                    while(left + 1 < states[i - 1].size() && states[i - 1][left + 1] <= states[i][j]){
                        ++left;
                        sum += fishes[i - 1][left];
                        best += fishes[i - 1][left];
                    }
                    best = max(best, max(dp_down[i - 2][leftt], dp_up[i - 2][leftt]) + sum);
                }
                dp_down[i][j] = max(dp_down[i][j], best);
                
            }
            
            best = 0;
            sum = accumulate(fishes[i - 1].begin(), fishes[i - 1].end(), 0ll);

            for(int j = sz - 1, left = states[i - 1].size(), leftt = states[i - 2].size(); j >= 0; --j){
                while(leftt - 1 > 0 && states[i - 2][leftt - 1] >= states[i][j]){
                    --leftt;
                    while(left - 1 > 0 && states[i - 1][left - 1] >= states[i - 2][leftt]){
                        --left;
                        sum -= fishes[i - 1][left];
                    }
                    best = max(best, max(dp_down[i - 2][leftt], dp_up[i - 2][leftt]) + sum);
                }
                
                dp_down[i][j] = max(dp_down[i][j], best);
            }
        }
    }


    return max(dp_up[n][0], dp_down[n][0]);
}   

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:36:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |                 while(left + 1 < states[i - 1].size() && states[i - 1][left + 1] <= states[i][j]){
      |                       ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
fish.cpp:57:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |                 while(leftt + 1 < states[i - 2].size() && states[i - 2][leftt + 1] <= states[i][j]){
      |                       ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
fish.cpp:59:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |                     while(left + 1 < states[i - 1].size() && states[i - 1][left + 1] <= states[i][j]){
      |                           ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• 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