Submission #961100

#	Time	Username	Problem	Language	Result	Execution time	Memory
961100		Pety	Izbori (COCI22_izbori)	C++14	110 / 110	593 ms	8016 KiB

Main

#include <bits/stdc++.h>
#define ll long long

using namespace std;

const int INF = 1e9;
const int MOD = 1e9 + 7;

int n, a[250002];
ll sol;

int idk[500005];

void divide (int st, int dr) {
  if (st == dr) {
    sol += 1;
    return;
  }
  int mid = (st + dr) / 2;
  divide(st, mid);
  divide(mid + 1, dr);
  map<int, int>fr;
  set<int>Maj;
  for (int i = mid; i >= st; i--) {
    fr[a[i]]++;
    if (fr[a[i]] >= (mid - i + 1) / 2 + 1)
      Maj.insert(a[i]);
  }
  fr.clear();
  for (int i = mid + 1; i <= dr; i++) {
    fr[a[i]]++;
    if (fr[a[i]] >= (i - mid) / 2 + 1)
      Maj.insert(a[i]);
  }
  int lim = (dr - st + 1);
  for (auto val : Maj) {
    int nr = 0;
    for (int i = mid; i >= st; i--) {
      if (a[i] == val)
        nr++;
      else
        nr--;
      idk[nr + lim]++;
    }
    for (int i = 2*lim; i >= 0; i--)
      idk[i] += idk[i + 1];
    nr = 0;
    for (int i = mid + 1; i <= dr; i++) {
      if (a[i] == val)
        nr++;
      else
        nr--;
      sol += idk[-nr + lim + 1];
    }
    for (int i = 2*lim; i >= 0; i--)
      idk[i] = 0;
  }
}

int main () 
{
  //ios_base::sync_with_stdio(false);
  //cin.tie(0); cout.tie(0);
  cin >> n;
  for (int i = 1; i <= n; i++)
    cin >> a[i];
  divide(1, n);
  cout << sol;
  
  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 70 / 70