Submission #65428

#	Time	Username	Problem	Language	Result	Execution time	Memory
65428		KieranHorgan	Pairs (IOI07_pairs)	C++17	37 / 100	221 ms	84500 KiB

pairs

#include <bits/stdc++.h>

using namespace std;
#define endl '\n'
#define ll long long
#define int long long
#define ld double
#define pii pair<int,int>
#define rand() abs((rand()<<15)|rand())
#define randll() abs(((long long)rand()<<30)

int B, N, D, M;
int n;

vector<vector<int>> rows;
struct SegmentTree {
  vector<vector<int>> st;
  SegmentTree(int N_) {
    n = N_;
    st.assign(4*n, vector<int>(0));
    build();
  }
  void build(int id=1, int l=0, int r=n) {
    if(l+1 == r) {
      st[id] = rows[l];
      return;
    }

    int mid = (l+r)/2;
    build(id*2  , l, mid);
    build(id*2+1, mid, r);
    merge(st[id*2].begin(), st[id*2].end(), st[id*2+1].begin(), st[id*2+1].end(), back_inserter(st[id]));
  }

  int query(int r1, int c1, int r2, int c2, int id=1, int l=0, int r=n) {
    if(l >= r1 && r <= r2) {
      for(auto x: st[id])
      return upper_bound(st[id].begin(), st[id].end(), c2)-lower_bound(st[id].begin(), st[id].end(), c1);
    }
    if(l >= r2 || r <= r1) return 0;

    int mid = (l+r)/2;
    return query(r1, c1, r2, c2, id*2  , l, mid) + query(r1, c1, r2, c2, id*2+1, mid, r);
  }
};

signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  cin >> B >> N >> D >> M;

  if(B == 1) {
    vector<int> a(N);
    for(auto &x: a)
      cin >> x;

    sort(a.begin(), a.end());

    int ans = 0;
    for(auto x: a)
      ans += upper_bound(a.begin(), a.end(), x+D)-lower_bound(a.begin(), a.end(), x-D)-1;

    cout << ans/2 << endl;
  }

  if(B == 2) {
    vector<pair<int, int>> a(N);
    rows.assign(2*M-1, vector<int>(0));
    for(int i = 0; i < N; i++) {
      int x, y;
      cin >> x >> y;
      x--; y--;
      rows[x+y].push_back(M-1-(x-y));
      a[i] = {x+y, M-1-(x-y)};
    }

    for(auto &v: rows)
      sort(v.begin(), v.end());

    SegmentTree st(2*M-1);
    int ans = 0;
    for(auto p: a) {
      ans += st.query(p.first-D, p.second-D, p.first+D+1, p.second+D)-1;
      int cur = 0;
      for(auto q: a)
        if(q != p && max(abs(p.first-q.first), abs(p.second-q.second)) <= D) {
          cur++;
        }
    }
    if(ans%2) return -1;
    cout << (ans)/2 << endl;
  }
}

Compilation message (stderr)

pairs.cpp: In member function 'long long int SegmentTree::query(long long int, long long int, long long int, long long int, long long int, long long int, long long int)':
pairs.cpp:37:16: warning: unused variable 'x' [-Wunused-variable]
       for(auto x: st[id])
                ^

• Subtask 1: 6 / 6
• Subtask 2: 6 / 6
• Subtask 3: 6 / 6
• Subtask 4: 6 / 6
• Subtask 5: 6 / 6
• Subtask 6: 0 / 7
• Subtask 7: 7 / 7
• Subtask 8: 0 / 8
• Subtask 9: 0 / 8
• Subtask 10: 0 / 10
• Subtask 11: 0 / 10
• Subtask 12: 0 / 10
• Subtask 13: 0 / 10