Submission #1250900

#	Time	Username	Problem	Language	Result	Execution time	Memory
1250900		nasjes	Feast (NOI19_feast)	C++20	12 / 100	1093 ms	21064 KiB

feast

#include <iostream>
#include <iomanip>
#include <vector>
#include <cmath>
#include <algorithm>
#include <set>
#include <queue>
#include <map>
#include <stack>
#include <bitset>
#include <string>
#include <cstring>
#include <iterator>
#include <random>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef long double ld;
const ll dim = 2*(1e6)+7;
//const ll mod = 1e9 + 7;
const ll inf = 1e17 + 77;
//#define endl "\n"
#define fi first
#define pb push_back
#define se second
#define vll vector<ll>

ll n, m, k;
ll t;
ll a[dim];
ll dp[dim];
int main() {

    ll  u, w,q,   v;
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin>>n>>k;
    set<pll> sml;
    set<pll> s;
    ll sm=0;
    ll fl=1;
    ll c=0;
    for(int i=1; i<=n; i++) {
        cin >> a[i];
        if (fl && a[i] >= 0) {
            sm += a[i];
        } else if (fl == 0 && a[i] < 0) {
            sm += a[i];
        } else {
            c++;
            s.insert({c, sm});
            sm=0;
            fl = 1 - fl;
            sm += a[i];
        }
    }

    c++;
    s.insert({c, sm});
    while(s.size()>0 && (*s.begin()).se<=0){
        s.erase(s.begin());
    }

    while(s.size()>0 && (*s.rbegin()).se<=0){
        auto it=(--s.end());
        s.erase(it);
    }
    m=s.size();
    m=(m+1)/2;
    ll ans=0;
    for(auto x: s){
        ll p1=x.fi;
        ll p2=x.se;
        //  cout<<p1<<" "<<p2<<endl;
        if(p2>0)ans+=x.se;
        sml.insert({abs(p2), p1});
    }
    //  cout<<ans<<endl;
    if(m<=k){
        cout<<ans<<endl;
        return 0;
    }
    else{
        m-=k;
    }
    while((s.size()+1)/2>k){
        pll cur=(*sml.begin());
        sml.erase(sml.begin());
/*        if((*s.rbegin()).se<0){
            s.erase((--s.end()));
        }
        if((*s.rbegin()).se<0){
            s.erase((--s.end()));
        }*/
        ll id=cur.se;
        auto it1=(s.lower_bound({id, -inf}));
        if(it1==(--s.end()) || it1==s.begin()){
            if((*it1).se>0)m--;
            s.erase(it1);
        }
        else{
            ll val=(*it1).se;
            auto it2=it1;
            it1++;
            it2--;
            pll x=(*it1);
            pll y=(*it2);
            s.erase(it1);
            s.erase(it2);
            sml.erase({abs(x.se), x.fi});
            sml.erase({abs(y.se), y.fi});
            s.insert({cur.se, x.se+y.se+val});
            sml.insert({abs( x.se+y.se+val), cur.se});
            m--;
        }
    }
    ans=0;
    for(auto x: s){
        if(x.se>0)ans+=x.se;
    }
    cout<<ans<<endl;



    return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 0 / 18
• Subtask 4: 0 / 10
• Subtask 5: 0 / 11
• Subtask 6: 0 / 20
• Subtask 7: 0 / 29