Submission #1023108

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023108		vjudge1	Catfish Farm (IOI22_fish)	C++17	84 / 100	970 ms	2097152 KiB

fish

#include "fish.h"
#include <bits/stdc++.h>

#pragma GCC optimize("Ofast")

using namespace std;

#define ll long long
#define pb push_back
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define sz(s) (int)s.size()
#define lb lower_bound
#define ub upper_bound
#define mem(a,i) memset(a,i,sizeof(a))

const int MAX=2e5+10;

int n;
vector<pair<ll,ll>> y[MAX];
vector<ll> p[MAX];
vector<vector<ll>> dp[MAX];
vector<ll> can[MAX];

ll getSum(int x,ll l,ll r){
    if(l>r)return 0;
    int L=lb(all(y[x]),make_pair(l,0ll))-y[x].begin();
    int R=ub(all(y[x]),make_pair(r+1,0ll))-y[x].begin()-1;
    if(L<=R){
        if(L==0)return p[x][R];
        return p[x][R]-p[x][L-1];
    }
    return 0;
}

vector<vector<ll>> sumF[MAX];
vector<vector<ll>> sumB[MAX];
vector<pair<int,int>> vec[MAX];
vector<vector<ll>> w;

struct t300{

    ll dp[3010][3010][2];

    ll getP(int i,int l,int r){
        if(l>r||i==0)return 0;
        return p[i][r]-p[i][l-1];
    }

    ll solve300(){
        for(int i=1;i<=n;i++){
            p[i].resize(n+10);
            p[i][0]=0;
            for(int j=1;j<=n;j++){
                p[i][j]=p[i][j-1]+w[i][j];
            }
        }
        mem(dp,0);
        for(int i=2;i<=n;i++){
            {
                ll mx=0;
                for(int j=n;j>=0;j--){
                    mx=max(mx,max(dp[i-1][j][0],dp[i-1][j][1])+p[i][j]);
                    dp[i][j][0]=mx-p[i][j];
                }

            }
            {
                ll mx=0;
                for(int j=0;j<=n;j++){
                    mx=max(mx,dp[i-1][j][1]-p[i-1][j]);
                    dp[i][j][1]=mx+p[i-1][j];
                    dp[i][j][1]=max(dp[i][j][1],dp[i-1][0][0]);
                }
                
            }
            // for(int j=0;j<=n;j++){
            //     {
            //         for(int f=0;f<=j;f++){
            //             dp[i][j][1]=max(dp[i][j][1],dp[i-1][f][1]+getP(i-1,f+1,j));
            //         }
            //         dp[i][j][1]=max(dp[i][j][1],dp[i-1][0][0]);
            //     }
            // }
        }
        ll ans=0;
        for(int j=0;j<=n;j++)ans=max(ans,max(dp[n][j][0],dp[n][j][1]));
        return ans;
    }
};


long long max_weights(int N, int M, vector<int> X, vector<int> Y,vector<int> W) {
    // assert(N<=300);
    n=N;
    int MX=0;
    bool sub=1;
    for(int i=0;i<M;i++){
        X[i]++;
        Y[i]++;
        y[X[i]].pb({Y[i],i});
        vec[Y[i]].pb({X[i],W[i]});
        sub&=(X[i]%2==1);
        MX=max(MX,X[i]);
    }
    if(sub){
        ll ans=0;
        for(int i=0;i<M;i++)ans+=W[i];
        return ans;
    }
    if(MX<=2){
        if(N==2){
            ll f=0,f1=0;
            for(int i=0;i<M;i++){
                if(X[i]%2)f+=W[i];
                else f1+=W[i];
            }
            return max(f,f1);
        }
        ll sum=0;
        for(int i=0;i<M;i++){
            if(X[i]%2==0)sum+=W[i];
        }
        ll ans=sum;
        for(int i=1;i<=N;i++){
            for(auto [x,w]:vec[i]){
                if(x%2==1)sum+=w;
                else sum-=w;
            }
            ans=max(ans,sum);
        }
        return ans;
    }
    for(int i=1;i<=N;i++){
        if(y[i].empty())continue;
        sort(all(y[i]));
        p[i].pb(W[y[i][0].S]);
        for(int j=1;j<sz(y[i]);j++){
            p[i].pb(p[i].back()+W[y[i][j].S]);
        }
    }
    if(N<=3000){
        w.resize(N+10);
        for(int i=1;i<=n;i++){
            w[i].resize(n+10);
            for(int j=1;j<=n;j++){
                w[i][j]=0;
            }
            for(auto [pos,num]:y[i])w[i][pos]=W[num];
        }
        t300 FFF;
        return FFF.solve300();
    }
    can[0].pb(0);
    can[N+1].pb(0);
    for(int i=1;i<=N;i++){
        can[i].pb(0);
        if(i>0){
            for(auto [x,b]:y[i-1])can[i].pb(x);
        }
        if(i+1<=N){
            for(auto [x,b]:y[i+1])can[i].pb(x);
        }
        sort(all(can[i]));
        can[i].erase(unique(all(can[i])),can[i].end());
    }
    for(int i=1;i<=N+1;i++){
        dp[i].resize(sz(can[i]));
        for(int j=0;j<sz(dp[i]);j++){
            dp[i][j].resize(sz(can[i-1]));
            for(int k=0;k<sz(can[i-1]);k++){
                dp[i][j][k]=0;
            }
        }
    }
    for(int i=0;i<N;i++){
        sumF[i].resize(sz(can[i]));
        for(int j=0;j<sz(can[i]);j++){
            sumF[i][j].resize(sz(can[i+1]));
            for(int k=0;k<sz(can[i+1]);k++){
                sumF[i][j][k]=getSum(i+1,can[i+1][k]+1,can[i][j]);
            }
        }
    }
    for(int i=1;i<=N+1;i++){
        sumB[i].resize(sz(can[i]));
        for(int j=0;j<sz(can[i]);j++){
            sumB[i][j].resize(sz(can[i-1]));
            for(int k=0;k<sz(can[i-1]);k++){
                sumB[i][j][k]=getSum(i-1,can[i-1][k]+1,can[i][j]);
            }
        }
    }
    for(int i=1;i<=N;i++){
        for(int j=0;j<sz(can[i]);j++){
            for(int k=0;k<sz(can[i-1]);k++){
                for(int f=0;f<sz(can[i+1]);f++){
                    ll nxt=dp[i][j][k];
                    {
                        nxt+=max(sumF[i-1][k][j],sumB[i+1][f][j]);
                    }
                    dp[i+1][f][j]=max(dp[i+1][f][j],nxt);
                }
            }
        }
    }
    ll ans=0;
    for(int j=0;j<sz(can[N]);j++)ans=max(ans,dp[N+1][0][j]);
    return ans;
}

• 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: 0 / 16