Submission #696666

#	Time	Username	Problem	Language	Result	Execution time	Memory
696666		SanguineChameleon	Izbori (COCI22_izbori)	C++17	110 / 110	160 ms	11576 KiB

Main

// BEGIN BOILERPLATE CODE
 
#include <bits/stdc++.h>
using namespace std;
 
#ifdef KAMIRULEZ
	const bool kami_loc = true;
	const long long kami_seed = 69420;
#else
	const bool kami_loc = false;
	const long long kami_seed = chrono::steady_clock::now().time_since_epoch().count();
#endif
 
const string kami_fi = "kamirulez.inp";
const string kami_fo = "kamirulez.out";
mt19937_64 kami_gen(kami_seed);
 
long long rand_range(long long rmin, long long rmax) {
	uniform_int_distribution<long long> rdist(rmin, rmax);
	return rdist(kami_gen);
}
 
long double rand_real(long double rmin, long double rmax) {
	uniform_real_distribution<long double> rdist(rmin, rmax);
	return rdist(kami_gen);
}
 
void file_io(string fi, string fo) {
	if (fi != "" && (!kami_loc || fi == kami_fi)) {
		freopen(fi.c_str(), "r", stdin);
	}
	if (fo != "" && (!kami_loc || fo == kami_fo)) {
		freopen(fo.c_str(), "w", stdout);
	}
}
 
void set_up() {
	if (kami_loc) {
		file_io(kami_fi, kami_fo);
	}
	ios_base::sync_with_stdio(0);
	cin.tie(0);
}
 
void just_do_it();
 
void just_exec_it() {
	if (kami_loc) {
		auto pstart = chrono::steady_clock::now();
		just_do_it();
		auto pend = chrono::steady_clock::now();
		long long ptime = chrono::duration_cast<chrono::milliseconds>(pend - pstart).count();
		string bar(50, '=');
		cout << '\n' << bar << '\n';
		cout << "Time: " << ptime << " ms" << '\n';
	}
	else {
		just_do_it();
	}
}
 
int main() {
	set_up();
	just_exec_it();
	return 0;
}
 
// END BOILERPLATE CODE
 
// BEGIN MAIN CODE
 
const int ms = 2e5 + 20;
const int block = 450;
int a[ms];
pair<int, int> p[ms];
vector<int> pos[ms];
int b[ms];
int cnt[ms * 2];
int n;
long long res;
 
void solve1(int C) {
	for (int i = 1; i <= n; i++) {
		b[i] = -1;
	}
	for (auto x: pos[C]) {
		b[x] = 1;
	}
	for (int i = -n; i <= n; i++) {
		cnt[i + ms] = 0;
	}
	long long tot = 0;
	int S = 0;
	cnt[ms] = 1;
	for (int i = 1; i <= n; i++) {
		if (b[i] == 1) {
			tot += cnt[S + ms];
			S++;
		}
		else {
			S--;
			tot -= cnt[S + ms];
		}
		cnt[S + ms]++;
		res += tot;
	}
}
 
void solve2(int C) {
	pos[C].push_back(n + 1);
	int sz = (int)pos[C].size() - 2;
	for (int i = 1; i <= sz; i++) {
		for (int j = i; j <= sz; j++) {
			int k = j - i + 1;
			int rem = (k - 1) - (pos[C][j] - pos[C][i] + 1 - k);
			if (rem < 0) {
				continue;
			}
			int lt = pos[C][i] - pos[C][i - 1] - 1;
			int rt = pos[C][j + 1] - pos[C][j] - 1;
			if (lt + rt <= rem) {
				res += 1LL * (lt + 1) * (rt + 1);
			}
			else if (rem <= rt) {
				int X = max(0, rem - lt + 1);
				int Y = rem + 1;
				res += 1LL * (X + Y) * (Y - X + 1) / 2;
			}
			else {
				int X = max(0, rem - lt + 1);
				int Y = rt + 1;
				res += 1LL * (X + Y) * (Y - X + 1) / 2;
				res += 1LL * (rt + 1) * (rem - rt);
			}
		}
	}
}
 
void just_do_it() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		p[i] = {a[i], i};
	}
	sort(p + 1, p + n + 1);
	int m = 0;
	for (int i = 1; i <= n; i++) {
		if (p[i].first != p[i - 1].first) {
			m++;
			pos[m].push_back(0);
		}
		a[p[i].second] = m;
	}
	for (int i = 1; i <= n; i++) {
		pos[a[i]].push_back(i);
	}
	for (int i = 1; i <= m; i++) {
		if ((int)pos[i].size() > block) {
			solve1(i);
		}
		else {
			solve2(i);
		}
	}
	cout << res;
}
 
// END MAIN CODE

Compilation message (stderr)

Main.cpp: In function 'void file_io(std::string, std::string)':
Main.cpp:30:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |   freopen(fi.c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:33:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |   freopen(fo.c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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