oj.uz

Submission #1079530

# Submission time Handle Problem Language Result Execution time Memory
1079530 2024-08-28T16:23:59 Z LittleOrange Radio Towers (IOI22_towers) C++17
17 / 100
 902 ms 97352 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.r]-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 380 ms 53772 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 1 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 1 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 663 ms 94892 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 213 ms 20824 KB Output is correct
2 Correct 862 ms 95432 KB Output is correct
3 Correct 821 ms 95432 KB Output is correct
4 Correct 828 ms 97224 KB Output is correct
5 Correct 902 ms 97224 KB Output is correct
6 Correct 829 ms 97220 KB Output is correct
7 Correct 858 ms 97224 KB Output is correct
8 Correct 704 ms 93712 KB Output is correct
9 Correct 700 ms 93796 KB Output is correct
10 Correct 655 ms 93544 KB Output is correct
11 Correct 676 ms 93748 KB Output is correct
12 Correct 127 ms 95500 KB Output is correct
13 Correct 147 ms 97224 KB Output is correct
14 Correct 130 ms 97228 KB Output is correct
15 Correct 94 ms 93784 KB Output is correct
16 Correct 93 ms 92784 KB Output is correct
17 Correct 117 ms 92056 KB Output is correct
18 Correct 119 ms 95436 KB Output is correct
19 Correct 145 ms 95408 KB Output is correct
20 Correct 139 ms 97224 KB Output is correct
21 Correct 137 ms 97352 KB Output is correct
22 Correct 143 ms 97220 KB Output is correct
23 Correct 153 ms 97312 KB Output is correct
24 Correct 123 ms 93736 KB Output is correct
25 Correct 89 ms 93736 KB Output is correct
26 Correct 104 ms 92972 KB Output is correct
27 Correct 135 ms 93784 KB Output is correct
28 Correct 2 ms 1624 KB Output is correct
29 Correct 3 ms 1624 KB Output is correct
30 Correct 2 ms 1624 KB Output is correct
31 Correct 2 ms 1624 KB Output is correct
32 Correct 3 ms 1624 KB Output is correct
33 Correct 1 ms 856 KB Output is correct
34 Correct 3 ms 1624 KB Output is correct
35 Correct 2 ms 1620 KB Output is correct
36 Correct 2 ms 1624 KB Output is correct
37 Correct 2 ms 1624 KB Output is correct
38 Correct 2 ms 1624 KB Output is correct
39 Correct 3 ms 1624 KB Output is correct
40 Correct 3 ms 1708 KB Output is correct
41 Correct 2 ms 1624 KB Output is correct
42 Correct 2 ms 1624 KB Output is correct
43 Correct 1 ms 1624 KB Output is correct

Subtask #6
0 / 19.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 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 380 ms 53772 KB 2nd lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -