Submission #627307

#	Time	Username	Problem	Language	Result	Execution time	Memory
627307		czhang2718	Catfish Farm (IOI22_fish)	C++17	100 / 100	210 ms	59896 KiB

fish

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

typedef long long ll;
#define f first
#define s second

const int N=3e5+4;
int n,m;
vector<pair<int,int>> fish[N];
vector<ll> dp[N], dp1[N], inc[N];

long long max_weights(int n, int m, std::vector<int> X, std::vector<int> Y,
                      std::vector<int> W) {
    for(int i=0; i<m; i++){
        fish[X[i]+1].push_back({Y[i], W[i]});
    }

    for(int i=1; i<=n; i++){
        fish[i].push_back({0, 0});
        fish[i].push_back({n, 0});
        sort(fish[i].begin(), fish[i].end());
        int p=fish[i].size();
        if(p>1 && fish[i][1].f==fish[i][0].f) fish[i].erase(fish[i].begin());
    }

    int i=0;
    fish[i].push_back({0, 0});
    dp[i].resize(2);
    dp1[i].resize(2);
    inc[i].resize(2);
    
    for(int i=1; i<=n; i++){
        int p=fish[i].size();
        dp[i].resize(p+1, -1e18);
        dp1[i].resize(p+1, -1e18);
        inc[i].resize(p+1, -1e18);
        ll sum=0;
        pair<int, ll> nxt={0,0}, prv={0,0};
        for(int j=0; j<p; j++){
            auto fi=fish[i][j];
            int y=fi.f, w=fi.s;
            while(nxt.f<fish[i+1].size() && fish[i+1][nxt.f].f+1<=y){
                nxt.s+=fish[i+1][nxt.f].s;
                nxt.f++;
            }
            while(prv.f<fish[i-1].size() && fish[i-1][prv.f].f+1<=y){
                prv.s+=fish[i-1][prv.f].s;
                prv.f++;
            }
            int k=upper_bound(fish[i-1].begin(), fish[i-1].end(), make_pair(y, int(1e9)))-fish[i-1].begin();
            dp[i][j]=max(dp1[i-1][k]-sum, prv.s+inc[i-1][k-1]);
            // cout << "inc " << prv.s+(fish[i-1][k-1].f?inc[i-1][k-1]:0) << "\n";
            int k2;
            if(i>=2){
                k2=upper_bound(fish[i-2].begin(), fish[i-2].end(), make_pair(y, int(1e9)))-fish[i-2].begin();
                dp[i][j]=max({dp[i][j], dp1[i-2][k2], dp[i-2][k2-1]+prv.s});
            }
            inc[i][j]=max(
                j?inc[i][j-1]:ll(-1e18), 
                -sum + max(prv.s+inc[i-1][k-1], i>=2?max(dp1[i-2][k2], dp[i-2][k2-1]+prv.s):0));
            sum+=w;
            // cout << "inc[" << i << "][" << j << "] " << inc[i][j] << "\n";
            // cout << "dp[" << i << "][" << j << "] " << dp[i][j] << "\n";
            dp1[i][j]=dp[i][j]+nxt.s;
            if(j) dp[i][j]=max(dp[i][j], dp[i][j-1]);
        }

        for(int j=p-1; j>=0; j--){
            dp1[i][j]=max(dp1[i][j+1], dp1[i][j]);
        }
    }


    return dp1[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:43:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |             while(nxt.f<fish[i+1].size() && fish[i+1][nxt.f].f+1<=y){
      |                   ~~~~~^~~~~~~~~~~~~~~~~
fish.cpp:47:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |             while(prv.f<fish[i-1].size() && fish[i-1][prv.f].f+1<=y){
      |                   ~~~~~^~~~~~~~~~~~~~~~~

• 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