oj.uz

Submission #1079527

# Submission time Handle Problem Language Result Execution time Memory
1079527 2024-08-28T16:22:22 Z LittleOrange Radio Towers (IOI22_towers) C++17
17 / 100
 917 ms 97496 KB 
#include "towers.h"

#include <vector>
#include<bits/stdc++.h>
using namespace std;
using ll = int;
const ll big = 1e9+10;
ll n;
ll w;
vector<ll> h,lh,rh,hh,hs,inc,decc;
//ll mx;
vector<ll> ps;
vector<pair<ll,ll>> rgs;
struct obj{
  ll v,c;
  bool operator<(const obj &o) const{
    return v<o.v;
  }
  bool operator>(const obj &o) const{
    return v>o.v;
  }
};
struct dat{
  ll c,l,r;
  dat():c(0),l(big),r(-big){}
  dat(ll x, ll y, ll z):c(x),l(y),r(z){}
  void put(ll i){
    c = 1;
    l = i;
    r = i;
  }
  dat operator+(const dat &o) const{
    return dat(c+o.c,min(l,o.l),max(r,o.r));
  }
};
struct node{
  ll l,r,m;
  dat v;
  node *L,*R;
  node(ll a, ll b):l(a),r(b),m(a+b>>1),v(),L(nullptr),R(nullptr){
    if(a<b){
      L = new node(l,m);
      R = new node(m+1,r);
    }
  }
  void put(ll i){
    if (l==r) v.put(i);
    else{
      if (i<=m) (L=new node(*L))->put(i);
      else (R=new node(*R))->put(i);
      v = L->v+R->v;
    }
  }
  dat qry(ll ql, ll qr){
    //cerr << "qry " << ql << " " << qr << " " << l << " " << r << " " << v.l << " " << v.r << " " << v.c << "\n"; 
    if (ql<=l&&r<=qr) return v;
    else{
      if (qr<=m) return L->qry(ql,qr);
      else if (ql>m) return R->qry(ql,qr);
      else return L->qry(ql,qr)+R->qry(ql,qr);
    }
  }
};
struct segtree{
  vector<node*> rt;
  segtree(){}
  segtree(ll n){
    rt.push_back(new node(0,n-1));
  }
  void nw(){
    rt.push_back(new node(*rt.back()));
  }
  void put(ll t, ll i){
    rt[t]->put(i);
  }
  dat qry(ll t, ll ql, ll qr){
    return rt[t]->qry(ql,qr);
  }
};
segtree t;

void init(int N, std::vector<int> H) {
  n = N;
  h = H;
  //for(ll i = 0;i<n;i++) if((i==0||(h[i-1]<h[i]))&&(i==n-1||h[i]>h[i+1])) mx = i;
  //for(ll i = 1;i<n-1;i++){
  //  if (h[i-1]<h[i]&&h[i]>h[i+1]){
  //    ps.push_back(i);
  //  }
  //}
  //for(auto [u,v] : ps) cerr << "[" << u << "," << v << "]" << " ";cerr << "\n";
  lh.resize(n,0);
  rh.resize(n,0);
  hh.resize(n,0);
  {
    vector<pair<ll,ll>> v;
    v.push_back({h[0],h[0]});
    for(ll i = 1;i<n;i++){
      ll mi = h[i];
      while(v.size()&&v.back().first<h[i]){
        mi = min(mi,v.back().second);
        v.pop_back();
      }
      lh[i] = h[i]-mi;
      v.push_back({h[i],mi});
    }
  }
  {
    vector<pair<ll,ll>> v;
    v.push_back({h[n-1],h[n-1]});
    for(ll i = n-2;i>=0;i--){
      ll mi = h[i];
      while(v.size()&&v.back().first<h[i]){
        mi = min(mi,v.back().second);
        v.pop_back();
      }
      rh[i] = h[i]-mi;
      v.push_back({h[i],mi});
    }
  }
  for(ll i = 0;i<n;i++) hh[i] = min(lh[i],rh[i]);
  hs = hh;
  sort(hs.begin(),hs.end());
  hs.erase(unique(hs.begin(),hs.end()),hs.end());
  t = segtree(n);
  w = hs.size();
  vector<vector<ll>> adds(w);
  for(ll i = 0;i<n;i++){
    ll p = lower_bound(hs.begin(),hs.end(),hh[i])-hs.begin();
    adds[p].push_back(i);
  }
  for(ll i = w-1;i>=0;i--){
    t.nw();
    for(ll j : adds[i]){
      t.put(w-i,j);
      //cerr << "add " << hs[i] << " " << j << "\n";
    }
    dat o = t.qry(w-i,0,n-1);
    //cerr << hs[i] << " " << o.l << " " << o.r << " " << o.c << "\n";
  }
  inc = decc = h;
  for(ll i = 1;i<n;i++) decc[i] = min(decc[i],decc[i-1]);
  for(ll i = n-2;i>=0;i--) inc[i] = min(inc[i],inc[i+1]);
}
bool ps_inited = false;
void init_ps(ll d){
  ps_inited = true;
  vector<ll> ld(n,big),rd(n,big);
  {
    vector<pair<ll,ll>> v;
    v.push_back({h[0],0});
    for(ll i = 1;i<n;i++){
      auto it = lower_bound(v.begin(),v.end(),make_pair(h[i]-d+1,0));
      if (it!=v.begin()) ld[i] = i-(*--it).second;
      while(v.size()&&v.back().first>h[i]) v.pop_back();
      v.push_back({h[i],i});
    }
  }
  {
    vector<pair<ll,ll>> v;
    v.push_back({h[n-1],n-1});
    for(ll i = n-2;i>=0;i--){
      auto it = lower_bound(v.begin(),v.end(),make_pair(h[i]-d+1,0));
      if (it!=v.begin()) rd[i] = (*--it).second-i;
      while(v.size()&&v.back().first>h[i]) v.pop_back();
      v.push_back({h[i],i});
    }
  }
  for(ll i = 0;i<n;i++) if(lh[i]>=d&&rh[i]>=d) {
    ps.push_back(i);
    rgs.push_back({i-ld[i],i+rd[i]});
    //cerr << i-ld[i] << " " << i << " " << i+rd[i] << "\n";
  }
}

int max_towers(int L, int R, int D) {
  if(!ps_inited) init_ps(D);
  ll l = L, r = R, d = D;
  ll ans = 1;
  ll idx = w-(lower_bound(hs.begin(),hs.end(),d)-hs.begin());
  dat o = t.qry(idx,L,R);
  //cerr << idx << " " << L << " " << R << " " << o.l << " " << o.r << " " << o.c << "\n";
  if (o.c==0) return 1;
  ll cur = o.c;
  ll l_need = upper_bound(inc.begin(),inc.end(),h[o.l]-d)-inc.begin();
  if (l_need-1<L) cur--;
  ll r_need = lower_bound(decc.begin(),decc.end(),h[o.l]-d,greater<ll>())-decc.begin();
  if (r_need>R) cur--;
  return 1+max(0,cur);
  //auto it0 = lower_bound(ps.begin(),ps.end(),r);
  //ll rf = it0-ps.begin();
  //auto it1 = lower_bound(ps.begin(),ps.end(),l+1);
  //ll lf = it1-ps.begin();
  //cerr << lf << " " << rf << "\n";
  //ans = max(0,rf-lf)+1;
  auto it0 = lower_bound(rgs.begin(),rgs.end(),make_pair(r,0));
  //if (it0!=rgs.begin()) --it0;
  ll rf = it0-rgs.begin();
  if (it0!=rgs.begin()){
    if ((*--it0).second>r) --rf;
  }
  auto it1 = lower_bound(rgs.begin(),rgs.end(),make_pair(l,0));
  ll lf = it1-rgs.begin();
  ans = max(0,rf-lf)+1;
  return ans;
  /*vector<obj> a,b;
  a.push_back({0,0});
  b.push_back({big,0});
  for(ll i = l;i<=r;i++){
    ll cur = 0;
    auto it = lower_bound(b.begin(),b.end(),obj({h[i]-1,0}),greater<obj>());
    --it;
    cur = (*it).c;
    ans = max(ans,cur+1);
    obj oa = {h[i],cur+1};
    if (a.size()<=oa.c) a.push_back(oa);
    else a[oa.c] = min(a[oa.c],oa);
    auto it0 = lower_bound(a.begin(),a.end(),obj({h[i]-d+1,0}));
    --it0;
    obj ob = {h[i]-d,(*it0).c};
    if (b.size()<=ob.c) b.push_back(ob);
    else b[ob.c] = max(b[ob.c],ob);
    ans = max(ans,cur+1);
    //cerr << "a:";for(auto [u,v] : a) cerr << "(" << u <<"," << v << ") ";cerr << "\n";
    //cerr << "b:";for(auto [u,v] : b) cerr << "(" << u <<"," << v << ") ";cerr << "\n";
  }*/
  return ans;
}

Compilation message

towers.cpp: In constructor 'node::node(ll, ll)':
towers.cpp:40:33: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   40 |   node(ll a, ll b):l(a),r(b),m(a+b>>1),v(),L(nullptr),R(nullptr){
      |                                ~^~
towers.cpp: In function 'void init(int, std::vector<int>)':
towers.cpp:138:9: warning: variable 'o' set but not used [-Wunused-but-set-variable]
  138 |     dat o = t.qry(w-i,0,n-1);
      |         ^

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 344 ms 53596 KB 2nd lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 600 KB 1st lines differ - on the 1st token, expected: '13', found: '15'
2 Halted 0 ms 0 KB -

Subtask #3
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 600 KB 1st lines differ - on the 1st token, expected: '13', found: '15'
2 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 650 ms 94920 KB 1st lines differ - on the 1st token, expected: '11903', found: '11904'
2 Halted 0 ms 0 KB -

Subtask #5
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 225 ms 20824 KB Output is correct
2 Correct 747 ms 95432 KB Output is correct
3 Correct 766 ms 95644 KB Output is correct
4 Correct 713 ms 97264 KB Output is correct
5 Correct 803 ms 97212 KB Output is correct
6 Correct 808 ms 97180 KB Output is correct
7 Correct 917 ms 97224 KB Output is correct
8 Correct 757 ms 93712 KB Output is correct
9 Correct 748 ms 93688 KB Output is correct
10 Correct 717 ms 93540 KB Output is correct
11 Correct 772 ms 93548 KB Output is correct
12 Correct 150 ms 95432 KB Output is correct
13 Correct 146 ms 97272 KB Output is correct
14 Correct 195 ms 97252 KB Output is correct
15 Correct 119 ms 93780 KB Output is correct
16 Correct 102 ms 92896 KB Output is correct
17 Correct 119 ms 92108 KB Output is correct
18 Correct 132 ms 95460 KB Output is correct
19 Correct 145 ms 95408 KB Output is correct
20 Correct 163 ms 97496 KB Output is correct
21 Correct 143 ms 97224 KB Output is correct
22 Correct 140 ms 97224 KB Output is correct
23 Correct 171 ms 97224 KB Output is correct
24 Correct 98 ms 93736 KB Output is correct
25 Correct 93 ms 93864 KB Output is correct
26 Correct 140 ms 92888 KB Output is correct
27 Correct 91 ms 93640 KB Output is correct
28 Correct 3 ms 1624 KB Output is correct
29 Correct 2 ms 1624 KB Output is correct
30 Correct 2 ms 1624 KB Output is correct
31 Correct 3 ms 1624 KB Output is correct
32 Correct 2 ms 1624 KB Output is correct
33 Correct 2 ms 856 KB Output is correct
34 Correct 2 ms 1624 KB Output is correct
35 Correct 2 ms 1624 KB Output is correct
36 Correct 2 ms 1624 KB Output is correct
37 Correct 3 ms 1624 KB Output is correct
38 Correct 2 ms 1624 KB Output is correct
39 Correct 2 ms 1624 KB Output is correct
40 Correct 2 ms 1624 KB Output is correct
41 Correct 2 ms 1620 KB Output is correct
42 Correct 2 ms 1624 KB Output is correct
43 Correct 2 ms 1624 KB Output is correct

Subtask #6
0 / 19.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 600 KB 1st lines differ - on the 1st token, expected: '13', found: '15'
2 Halted 0 ms 0 KB -

Subtask #7
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 344 ms 53596 KB 2nd lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -