Submission #960783

#	Time	Username	Problem	Language	Result	Execution time	Memory
960783		Trisanu_Das	Event Hopping (BOI22_events)	C++17	Compilation error	0 ms	0 KiB

events

#include <bits/stdc++.h>
using namespace std ;
 
int n, q, l[100005], r[100005], bin[18][100005];
vector<int> v, s;
 
int bin_s(int x){
  int lo = -1, hi = s.size() - 1;
  while(hi - lo > 1){
    int mid = (hi + lo) / 2;
    if(r[s[mid]] >= x) hi = mid;
    else lo = mid;
  }
  return s[hi];
}
 
bool cmp(int x, int y){
  if(r[x] != r[y]) return r[x] < r[y];
  return l[x] < l[y];
}
 
int solve(int b, int x, int y){
  if(b == -1) return 0;
  int cur = bin[b][x];
  if(l[cur] > r[y]) return (1 << b) + solve(b - 1, cur, y);
  return solve(b - 1, x, y);
}
 
int main() {
  ios_base::sync_with_stdio(false); cin.tie(nullptr);
  cin >> n >> q  ;
  for(int i = 1; i <= n; i++) {
    cin >> l[i] >> r[i];
    v.push_back(i);
  }
  sort(v.begin(), v.end(), cmp);
  for(int i = 1; i <= n; i++){
    int u = v[i];
    for(!s.empty() && l[s.back()] >= l[u]) s.pop_back();
    s.push_back(u);
    bin[0][u] = bin_s(u);
  }
  for(int i = 1; i < 18; i++) for(int j = 1; j <= n; j++) bin[i][j] = bin[i - 1][bin[i - 1][j]];
  while(q--){
    int x, y; cin >> x >> y;
    if(l[bin[17][y]] > r[x] || r[y] < r[x]){
      cout << "impossible\n"; continue;
    }
    if(x == y){
      cout << 0 << '\n'; continue;
    }
    if(l[y] <= r[x]){
      cout << 1 << '\n'; continue;
    }
    cout << 2 + solve(17, y, x) << '\n';
  }
}

Compilation message (stderr)

events.cpp: In function 'int main()':
events.cpp:39:42: error: expected ';' before ')' token
   39 |     for(!s.empty() && l[s.back()] >= l[u]) s.pop_back();
      |                                          ^
      |                                          ;
events.cpp:40:16: error: could not convert 's.std::vector<int>::push_back(u)' from 'void' to 'bool'
   40 |     s.push_back(u);
      |     ~~~~~~~~~~~^~~
      |                |
      |                void
events.cpp:41:25: error: expected ')' before ';' token
   41 |     bin[0][u] = bin_s(u);
      |                         ^
      |                         )
events.cpp:39:8: note: to match this '('
   39 |     for(!s.empty() && l[s.back()] >= l[u]) s.pop_back();
      |        ^