Submission #1068509

#	Time	Username	Problem	Language	Result	Execution time	Memory
1068509		Unforgettablepl	Catfish Farm (IOI22_fish)	C++17	52 / 100	1118 ms	1909328 KiB

fish

#include "fish.h"
#include <bits/stdc++.h>
using namespace std;

long long max_weights(int N, int M,vector<int> X,vector<int> Y,
                      vector<int> W){
    vector DP(N+1,vector(N+1,vector(2,0ll)));
    // vector<vector<pair<int,int>>> pref(N+2);
    // for(int i=1;i<=N+1;i++)pref[i].emplace_back(0,0);
    vector<vector<int>> special_points(N+2);
    for(int i=1;i<=N+1;i++)special_points[i].emplace_back(0);
    for(int i=1;i<=N+1;i++)special_points[i].emplace_back(N);
    vector transition1(N+1,vector(N+1,0ll));
    vector transition2(N+1,vector(N+1,0ll));
    vector transition3(N+1,vector(N+1,0ll));
    vector transition4(N+1,vector(N+1,0ll));
    // for(int i=0;i<M;i++) {
    //     pref[X[i]+1].emplace_back(Y[i]+1,W[i]);
    //     special_points[X[i]+1].emplace_back(Y[i]);
    // }
    // for(int i=1;i<=N+1;i++) {
    //     sort(special_points[i].begin(),special_points[i].end());
    //     sort(pref[i].begin(), pref[i].end());
    //     for(int j=1;j<pref[i].size();j++)pref[i][j].second+=pref[i][j-1].second;
    // }
    vector pref(N+2,vector(N+1,0ll));
    for(int i=0;i<M;i++) {
        pref[X[i]+1][Y[i]+1]=W[i];
    }
    for(int i=1;i<=N;i++)for(int j=1;j<=N;j++)pref[i][j]+=pref[i][j-1];
    auto getpref = [&](int i,int j) {
        return pref[i][j];
        // auto iter = lower_bound(pref[i].begin(),pref[i].end(),make_pair(j+1,-1));
        // iter--;
        // return iter->second;
    };
    for(int i=2;i<=N;i++) {
        for(int j=0;j<=N;j++) {
            if(i!=2)DP[i][j][1]=max(DP[i][j][1],-getpref(i,j)+transition1[i-1][j]);
            else {
                for(int x=j;x<=N;x++) {
                    DP[i][j][1]=max(DP[i][j][1],getpref(i,x)-getpref(i,j)+max(DP[i-1][x][0],DP[i-1][x][1]));
                }
            }
            if(i>2) {
                if(i!=3) {
                    DP[i][j][0]=max(DP[i][j][0],getpref(i-1,j)+transition2[i-2][j]);
                    DP[i][j][0]=max(DP[i][j][0],transition3[i-2][j]);
                }
                else for(int x=0;x<=N;x++) {
                    DP[i][j][0]=max(DP[i][j][0],getpref(i-1,max(x,j))+max(DP[i-2][x][0],DP[i-2][x][1]));
                }
            }
            if(i!=2)DP[i][j][0]=max(DP[i][j][0],getpref(i-1,j)+transition4[i-1][j]);
            else for(int x=0;x<=j;x++) {
                DP[i][j][0]=max(DP[i][j][0],getpref(i-1,j)-getpref(i-1,x)+DP[i-1][x][0]);
            }
            transition1[i][j]=getpref(i+1,j)+max(DP[i][j][0],DP[i][j][1]);
            transition2[i][j]=max(DP[i][j][0],DP[i][j][1]);
            transition3[i][j]=getpref(i+1,j)+max(DP[i][j][0],DP[i][j][1]);
            transition4[i][j]=-getpref(i,j)+DP[i][j][0];
        }
        for(int j=N-1;j>=0;j--)transition1[i][j]=max(transition1[i][j],transition1[i][j+1]);
        for(int j=1;j<=N;j++)transition2[i][j]=max(transition2[i][j],transition2[i][j-1]);
        for(int j=N-1;j>=0;j--)transition3[i][j]=max(transition3[i][j],transition3[i][j+1]);
        for(int j=1;j<=N;j++)transition4[i][j]=max(transition4[i][j],transition4[i][j-1]);
    }
    long long ans = 0;
    for(int j=0;j<=N;j++)ans=max(ans,DP[N][j][0]);
    for(int j=0;j<=N;j++)ans=max(ans,DP[N][j][1]);
    return ans;
}

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