Submission #1223426

#	Time	Username	Problem	Language	Result	Execution time	Memory
1223426		duyanhloveav	Poklon (COCI17_poklon)	C++20	140 / 140	213 ms	28944 KiB

poklon

#include <bits/stdc++.h>
using namespace std;

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1LL)

using ll = long long;

const int mxn = 9 + 1e6;
const int inf = 0x3f3f3f3f;
const ll lnf = 0x3f3f3f3f3f3f3f3f;

template<class T>
struct Fenwick {
  vector<T> fenw;
  int n;
  Fenwick(int n): n(n) {
    fenw.resize(n);
  }

  void upd(int x, T v) {
    for (; x < n; x |= x + 1) {
      fenw[x] += v;
    }
  }

  T get(int x) {
    T v{};
    for (; x >= 0; x &= x + 1, --x) {
      v += fenw[x];
    }
    return v;
  }
};

void _27augain(void) {
  int n, q;
  cin >> n >> q;
  map<int, int> mp;
  vector<int> p(n + 1);
  for (int i = 1; i <= n; ++i) {
    int r;
    cin >> r;
    p[i] = mp[r];
    mp[r] = i;
  }
  vector<vector<array<int, 2>>> query(n + 1);
  for (int i = 0; i < q; ++i) {
    int l, r;
    cin >> l >> r;
    query[r].push_back({l, i});
  }
  Fenwick<int> fenw(n + 1);
  vector<int> res(q);
  for (int r = 1; r <= n; ++r) {
    fenw.upd(p[r], 1), fenw.upd(p[p[r]], -2), fenw.upd(p[p[p[r]]], 1);
    for (auto [l, i] : query[r]) {
      res[i] = fenw.get(r) - fenw.get(l - 1);
    }
  }
  for (auto &x : res) {
    cout << x << "\n";
  }
}

int32_t main(void) {
#define task "27augain"
  cin.tie(0)->sync_with_stdio(0);
  for (string iext : {"in", "inp"}) {
    if (fopen((task "." + iext).c_str(), "r")) {
      freopen((task "." + iext).c_str(), "r", stdin);
      freopen(task ".out", "w", stdout);
    }
  }
  int testcase = 1;
  // cin >> testcase;
  while (testcase--) {
    _27augain();
  }
  return 0;
}

Compilation message (stderr)

poklon.cpp: In function 'int32_t main()':
poklon.cpp:71:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |       freopen((task "." + iext).c_str(), "r", stdin);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
poklon.cpp:72:14: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |       freopen(task ".out", "w", stdout);
      |       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 140 / 140