Submission #696447

#	Time	Username	Problem	Language	Result	Execution time	Memory
696447		SanguineChameleon	Osmosmjerka (COCI17_osmosmjerka)	C++17	140 / 160	2225 ms	56400 KiB

osmosmjerka

// 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 long long mod = 998244353;
const long long base = 31;
const int ms = 5e2 + 20;
const int st = 30;
const int dx[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
const int dy[8] = {-1, 0, 1, -1, 1, -1, 0, 1};
int a[ms][ms];
int pw[st];
int h[ms][ms][st];

void just_do_it() {
	int n, m, L;
	cin >> n >> m >> L;
	pw[0] = base;
	for (int i = 1; i < st; i++) {
		pw[i] = 1LL * pw[i - 1] * pw[i - 1] % mod;
	}
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			char c;
			cin >> c;
			a[i][j] = c - 'a';
			for (int d = 0; d < 8; d++) {
				h[i][j][0] = a[i][j] + 1;
			}
		}
	}
	map<int, int> cnt;
	for (int d = 0; d < 8; d++) {
		for (int k = 1; k < st; k++) {
			for (int i = 0; i < n; i++) {
				for (int j = 0; j < m; j++) {
					int ni = (i + dx[d] * (1 << (k - 1))) % n;
					if (ni < 0) {
						ni += n;
					}
					int nj = (j + dy[d] * (1 << (k - 1))) % m;
					if (nj < 0) {
						nj += m;
					}
					h[i][j][k] = (1LL * h[i][j][k - 1] * pw[k - 1] + h[ni][nj][k - 1]) % mod;
				}
			}
		}
		for (int i = 0; i < n; i++) {
			for (int j = 0; j < m; j++) {
				int ci = i;
				int cj = j;
				int X = 0;
				for (int k = 0; k < st; k++) {
					if ((L >> k) & 1) {
						X = (1LL * X * pw[k] + h[ci][cj][k]) % mod;
						ci = (ci + dx[d] * (1 << k)) % n;
						if (ci < 0) {
							ci += n;
						}
						cj = (cj + dy[d] * (1 << k)) % m;
						if (cj < 0) {
							cj += m;
						}
					}
				}
				cnt[X]++;
			}
		}
	}
	long long den = 1LL * (n * m) * (n * m) * 64;
	long long num = 0;
	for (auto p: cnt) {
		num += 1LL * p.second * p.second;
	}
	long long g = __gcd(num, den);
	num /= g;
	den /= g;
	cout << num << "/" << den;
}

// END MAIN CODE

Compilation message (stderr)

osmosmjerka.cpp: In function 'void file_io(std::string, std::string)':
osmosmjerka.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);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
osmosmjerka.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: 140 / 160