Submission #603278

#	Time	Username	Problem	Language	Result	Execution time	Memory
603278		AdamGS	Feast (NOI19_feast)	C++17	100 / 100	179 ms	120688 KiB

feast

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
struct Node {
  ll pref;
  int ind_pref;
  ll inv_pref;
  int inv_ind_pref;
  ll suf;
  int ind_suf;
  ll inv_suf;
  int inv_ind_suf;
  ll psoms;
  int indl_psoms, indr_psoms;
  ll inv_psoms;
  int inv_indl_psoms, inv_indr_psoms;
  ll sum;
  int lazy;
};
const int LIM=1<<20, INF=1e9+7;
ll T[LIM], N=1, n, k;
Node tr[2*LIM], pusty;
void inv(int v) {
  swap(tr[v].pref, tr[v].inv_pref);
  swap(tr[v].ind_pref, tr[v].inv_ind_pref);
  swap(tr[v].suf, tr[v].inv_suf);
  swap(tr[v].ind_suf, tr[v].inv_ind_suf);
  swap(tr[v].psoms, tr[v].inv_psoms);
  swap(tr[v].indl_psoms, tr[v].inv_indl_psoms);
  swap(tr[v].indr_psoms, tr[v].inv_indr_psoms);
  tr[v].sum*=-1;
  tr[v].lazy^=1;
}
void spl(int v) {
  inv(2*v);
  inv(2*v+1);
  tr[v].lazy=0;
}
void lacz(int v) {
  tr[v].pref=tr[2*v].pref; tr[v].ind_pref=tr[2*v].ind_pref;
  if(tr[2*v].sum+tr[2*v+1].pref>tr[v].pref) {
    tr[v].pref=tr[2*v].sum+tr[2*v+1].pref;
    tr[v].ind_pref=tr[2*v+1].ind_pref;
  }
  tr[v].suf=tr[2*v+1].suf; tr[v].ind_suf=tr[2*v+1].ind_suf;
  if(tr[2*v+1].sum+tr[2*v].suf>tr[v].suf) {
    tr[v].suf=tr[2*v+1].sum+tr[2*v].suf;
    tr[v].ind_suf=tr[2*v].ind_suf;
  }
  tr[v].psoms=tr[2*v].psoms; 
  tr[v].indl_psoms=tr[2*v].indl_psoms; tr[v].indr_psoms=tr[2*v].indr_psoms;
  if(tr[2*v+1].psoms>tr[v].psoms) {
    tr[v].psoms=tr[2*v+1].psoms;
    tr[v].indl_psoms=tr[2*v+1].indl_psoms; tr[v].indr_psoms=tr[2*v+1].indr_psoms;
  }
  if(tr[2*v].suf+tr[2*v+1].pref>tr[v].psoms) {
    tr[v].psoms=tr[2*v].suf+tr[2*v+1].pref;
    tr[v].indl_psoms=tr[2*v].ind_suf; tr[v].indr_psoms=tr[2*v+1].ind_pref;
  }
  tr[v].inv_pref=tr[2*v].inv_pref; tr[v].inv_ind_pref=tr[2*v].inv_ind_pref;
  if(-tr[2*v].sum+tr[2*v+1].inv_pref>tr[v].inv_pref) {
    tr[v].inv_pref=-tr[2*v].sum+tr[2*v+1].inv_pref;
    tr[v].inv_ind_pref=tr[2*v+1].inv_ind_pref;
  }
  tr[v].inv_suf=tr[2*v+1].inv_suf; tr[v].inv_ind_suf=tr[2*v+1].inv_ind_suf;
  if(-tr[2*v+1].sum+tr[2*v].inv_suf>tr[v].inv_suf) {
    tr[v].inv_suf=-tr[2*v+1].sum+tr[2*v].inv_suf;
    tr[v].inv_ind_suf=tr[2*v].inv_ind_suf;
  }
  tr[v].inv_psoms=tr[2*v].inv_psoms; 
  tr[v].inv_indl_psoms=tr[2*v].inv_indl_psoms; tr[v].inv_indr_psoms=tr[2*v].inv_indr_psoms;
  if(tr[2*v+1].inv_psoms>tr[v].inv_psoms) {
    tr[v].inv_psoms=tr[2*v+1].inv_psoms;
    tr[v].inv_indl_psoms=tr[2*v+1].inv_indl_psoms; tr[v].inv_indr_psoms=tr[2*v+1].inv_indr_psoms;
  }
  if(tr[2*v].inv_suf+tr[2*v+1].inv_pref>tr[v].inv_psoms) {
    tr[v].inv_psoms=tr[2*v].inv_suf+tr[2*v+1].inv_pref;
    tr[v].inv_indl_psoms=tr[2*v].inv_ind_suf; tr[v].inv_indr_psoms=tr[2*v+1].inv_ind_pref;
  }
  tr[v].sum=tr[2*v].sum+tr[2*v+1].sum;
}
void upd(int v, int l, int r, int a, int b) {
  if(b<l || a>r) return;
  if(a<=l && r<=b) {
    inv(v);
    return;
  }
  if(tr[v].lazy) spl(v);
  int mid=(l+r)/2;
  upd(2*v, l, mid, a, b);
  upd(2*v+1, mid+1, r, a, b);
  lacz(v);
}
ll dynamiczny_psoms(int x) {
  rep(i, 2*N) tr[i]=pusty;
  rep(i, n) tr[N+i]={T[i], i, -T[i], i, T[i], i, -T[i], i, T[i], i, i, -T[i], i, i, T[i], 0};
  for(int i=N-1; i; --i) lacz(i);
  ll ans=0;
  while(x--) {
    if(tr[1].psoms<=0) break;
    ans+=tr[1].psoms;
    upd(1, 0, N-1, tr[1].indl_psoms, tr[1].indr_psoms);
  }
  return ans;
}
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  cin >> n >> k;
  k=min(n, k);
  while(N<n) N*=2;
  rep(i, n) cin >> T[i];
  cout << dynamiczny_psoms(k) << '\n';
}

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