oj.uz

Submission #1079469

# Submission time Handle Problem Language Result Execution time Memory
1079469 2024-08-28T15:24:29 Z LittleOrange Radio Towers (IOI22_towers) C++17
14 / 100
 701 ms 3536 KB 
#include "towers.h"

#include <vector>
#include<bits/stdc++.h>
using namespace std;
using ll = int;
const ll big = 1e9+10;
ll n;
vector<ll> h;
//ll mx;
vector<ll> ps;
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;
  }
};

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";
}
bool ps_inited = false;
void init_ps(ll d){
  ps_inited = true;
  vector<ll> l(n,0),r(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();
      }
      if (mi<=h[i]-d) l[i] = 1;
      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();
      }
      if (mi<=h[i]-d) r[i] = 1;
      v.push_back({h[i],mi});
    }
  }
  for(ll i = 0;i<n;i++) if(l[i]&&r[i]) ps.push_back(i);
}

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;
  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";
  return max(0,rf-lf)+1;
  /*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 function 'int max_towers(int, int, int)':
towers.cpp:68:20: warning: unused variable 'd' [-Wunused-variable]
   68 |   ll l = L, r = R, d = D;
      |                    ^

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 268 ms 2156 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 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Incorrect 1 ms 344 KB 1st lines differ - on the 1st token, expected: '91', found: '92'
4 Halted 0 ms 0 KB -

Subtask #3
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Incorrect 1 ms 344 KB 1st lines differ - on the 1st token, expected: '91', found: '92'
4 Halted 0 ms 0 KB -

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 442 ms 2260 KB Output is correct
2 Correct 684 ms 2236 KB Output is correct
3 Correct 701 ms 2256 KB Output is correct
4 Correct 657 ms 2256 KB Output is correct
5 Correct 655 ms 2256 KB Output is correct
6 Correct 645 ms 2252 KB Output is correct
7 Correct 661 ms 2256 KB Output is correct
8 Correct 681 ms 3536 KB Output is correct
9 Correct 606 ms 3536 KB Output is correct
10 Correct 619 ms 3532 KB Output is correct
11 Correct 608 ms 3536 KB Output is correct
12 Correct 631 ms 3528 KB Output is correct
13 Correct 623 ms 3536 KB Output is correct
14 Correct 0 ms 344 KB Output is correct
15 Correct 1 ms 344 KB Output is correct
16 Correct 1 ms 344 KB Output is correct
17 Correct 13 ms 2332 KB Output is correct
18 Correct 12 ms 2256 KB Output is correct
19 Correct 12 ms 2256 KB Output is correct
20 Correct 11 ms 3536 KB Output is correct
21 Correct 11 ms 3536 KB Output is correct
22 Correct 13 ms 2228 KB Output is correct
23 Correct 12 ms 2256 KB Output is correct
24 Correct 11 ms 2232 KB Output is correct
25 Correct 17 ms 3364 KB Output is correct
26 Correct 11 ms 3536 KB Output is correct
27 Correct 1 ms 344 KB Output is correct
28 Correct 0 ms 344 KB Output is correct
29 Correct 0 ms 344 KB Output is correct
30 Correct 1 ms 344 KB Output is correct
31 Correct 0 ms 344 KB Output is correct
32 Correct 1 ms 344 KB Output is correct
33 Correct 1 ms 344 KB Output is correct
34 Correct 1 ms 344 KB Output is correct
35 Correct 1 ms 344 KB Output is correct
36 Correct 0 ms 344 KB Output is correct

Subtask #5
0 / 17.0

# Verdict Execution time Memory Grader output
1 Incorrect 182 ms 852 KB 2nd lines differ - on the 1st token, expected: '7063', found: '7197'
2 Halted 0 ms 0 KB -

Subtask #6
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Incorrect 1 ms 344 KB 1st lines differ - on the 1st token, expected: '91', found: '92'
4 Halted 0 ms 0 KB -

Subtask #7
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 268 ms 2156 KB 2nd lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -