Submission #1023970

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023970		Otalp	Catfish Farm (IOI22_fish)	C++17	100 / 100	739 ms	249244 KiB

fish

#include "fish.h"
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define ll long long
#define pii pair<int, int>
#define ff first
#define ss second

const int MAXN = 500100;
int n, w[MAXN], m;
pii a[MAXN];

namespace B{
    unordered_map<ll, ll> d[200100];
    unordered_map<ll, ll> dp[200100];
    unordered_map<ll, ll> pref[200100];
    unordered_map<ll, ll> ddp[200100];
    vector<ll> pos[200100];
    ll suf[200100];
    ll solve(){
        for(ll i=1; i<=m; i++){
            d[a[i].ff][a[i].ss] += w[i];
        }
        for(int i=0; i<=n; i++){
            d[i][0] += 0;
            d[i][n] += 0;
        }
        for(int i=0; i<=n; i++){
            for(auto h: d[i]){
                pos[i].pb(h.ff);
            }
        }
        for(ll i=1; i<=n; i++){
            sort(pos[i].begin(), pos[i].end());
        }
        for(ll i=1; i<=n; i++){
            dp[0][i] = -1e18;
            ddp[0][i] = -1e18;
        }
        dp[0][0] = 0;
        ddp[0][0] = 0;
        for(ll i=1; i<=n; i++){
            //cout<<"_____________________\n";
            //cout<<i<<'\n';
            vector<ll> alpos;
            for(auto h: pos[i-1]) alpos.pb(h);
            for(auto h: pos[i+1]) alpos.pb(h);
            sort(alpos.begin(), alpos.end());
            int gls = 0;
            for(ll  h: pos[i]){
                ll j = h;
                pref[i][j] = pref[i][gls] + d[i][j];
                gls = j;
            }
            vector<ll> dpos;
            for(auto h: dp[i-1]){
                dpos.pb(h.ff);
            }
            sort(dpos.begin(), dpos.end());
            ll mx = -1e18;
            ll ls = pos[i].size()-1;
            for(ll h = dpos.size()-1; h>=0; h--){
                ll j = dpos[h];
                while(ls > 0 and pos[i][ls] > j) ls--;
                mx = max(mx, dp[i-1][j] + pref[i][j]);
                suf[j] = mx;
            }
            ll pddp = -1e18, pdp = -1e18;
            mx = -1e18;
            for(ll h = dpos.size()-1; h>=0; h--){
                ll j = dpos[h];
                mx = max(mx, dp[i-1][j]);
            }
            ll pls=-1, dpls=-1;
            ls = -1;
            ll lls = -1;
            for(ll j: alpos){
                //cout<<j<<' ';
                while(ls + 1 < dpos.size() and dpos[ls + 1] <= j){
                    ls += 1;
                    while(lls + 1 < pos[i-1].size() and pos[i-1][lls + 1] <= dpos[ls]) lls++;
                    pdp = max(pdp, ddp[i-1][dpos[ls]]-pref[i-1][pos[i-1][lls]]);
                }
                while(pls + 1 < pos[i].size() and pos[i][pls + 1] <= j) pls ++;
                while(dpls + 1 < pos[i-1].size() and pos[i-1][dpls + 1] <= j) dpls ++;
                ddp[i][j] = mx;
                dp[i][j] = 0;
                //if(dpls < 0){
                //    cout<<"asdas\n";
                //    cout<<j<<'\n';
                //    cout<<dpls+1<<'\n';
                //    continue;
                //}
                ddp[i][j] = max(ddp[i][j], pdp + pref[i-1][pos[i-1][dpls]]);
                dp[i][j] = ddp[i][j];
                if(dpos.size() > ls + 1) dp[i][j] = max(dp[i][j], suf[dpos[ls + 1]]-pref[i][pos[i][pls]]);
                else dp[i][j] = max(dp[i][j], suf[dpos[ls]]-pref[i][pos[i][pls]]);
                dp[i][j] = max(dp[i][j], pdp+pref[i-1][pos[i-1][dpls]]);
            }
            //cout<<'\n';
        }
        //for(ll i=1; i<=n; i++){
        //    for(ll j=0; j<=n; j++){
        //        cout<<pref[i][j]<<' ';
        //    }
        //    cout<<'\n';
        //}
        ll ans = 0;
        for(ll i=0; i<=n; i++) ans = max(ans, dp[n][i]);
        return ans;
    }
}




long long max_weights(int N, int M, vector<int> X, vector<int> Y,
                      vector<int> W) {
    
    n = N;
    m = M;
    for(int i=1; i<=m; i++){
        a[i] = {X[i-1]+1, Y[i-1]+1};
    }
    for(int i=1; i<=m; i++){
        w[i] = W[i-1];
    }
    return B::solve();
}

Compilation message (stderr)

fish.cpp: In function 'long long int B::solve()':
fish.cpp:80:30: 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]
   80 |                 while(ls + 1 < dpos.size() and dpos[ls + 1] <= j){
      |                       ~~~~~~~^~~~~~~~~~~~~
fish.cpp:82:35: 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]
   82 |                     while(lls + 1 < pos[i-1].size() and pos[i-1][lls + 1] <= dpos[ls]) lls++;
      |                           ~~~~~~~~^~~~~~~~~~~~~~~~~
fish.cpp:85:31: 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]
   85 |                 while(pls + 1 < pos[i].size() and pos[i][pls + 1] <= j) pls ++;
      |                       ~~~~~~~~^~~~~~~~~~~~~~~
fish.cpp:86:32: 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]
   86 |                 while(dpls + 1 < pos[i-1].size() and pos[i-1][dpls + 1] <= j) dpls ++;
      |                       ~~~~~~~~~^~~~~~~~~~~~~~~~~
fish.cpp:97:32: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   97 |                 if(dpos.size() > ls + 1) dp[i][j] = max(dp[i][j], suf[dpos[ls + 1]]-pref[i][pos[i][pls]]);
      |                    ~~~~~~~~~~~~^~~~~~~~
fish.cpp:69:16: warning: unused variable 'pddp' [-Wunused-variable]
   69 |             ll pddp = -1e18, pdp = -1e18;
      |                ^~~~

• 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