Submission #1163299

#	Time	Username	Problem	Language	Result	Execution time	Memory
1163299		xnscdev	Osmosmjerka (COCI17_osmosmjerka)	C++20	140 / 160	2065 ms	327680 KiB

osmosmjerka

// https://oj.uz/problem/view/COCI17_osmosmjerka

#ifndef DEBUG
#pragma GCC optimize("Ofast,unroll-loops")
#endif

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/trie_policy.hpp>

#if defined(DEBUG) && defined(DEBUG_UTIL)
#include "dsa_util.h"
#endif

// clang-format off
using namespace std;
using namespace __gnu_pbds;
using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;

constexpr int INF = 0x3f3f3f3f;
constexpr ll INFL = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-9;
constexpr int dx[8] = {1, -1, 0, 0, 1, 1, -1, -1};
constexpr int dy[8] = {0, 0, 1, -1, 1, -1, 1, -1};
constexpr int drev[8] = {1, 0, 3, 2, 7, 6, 5, 4};
constexpr int drotl[8] = {2, 3, 1, 0, 6, 4, 7, 5};
constexpr int drotr[8] = {3, 2, 0, 1, 5, 7, 4, 6};
constexpr char dn_nsew[4] = {'S', 'N', 'E', 'W'};
constexpr char dn_udrl[4] = {'D', 'U', 'R', 'L'};
unordered_map<char, int> dm_nsew = {{'S', 0}, {'N', 1}, {'E', 2}, {'W', 3}};
unordered_map<char, int> dm_udrl = {{'D', 0}, {'U', 1}, {'R', 2}, {'L', 3}};
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

#if __cplusplus < 202002L
template <typename T> int popcount(T x); template <> int popcount(uint x) { return __builtin_popcount(x); } template <> int popcount(ull x) { return __builtin_popcountll(x); }
template <typename T> int countl_zero(T x); template <> int countl_zero(uint x) { return __builtin_clz(x); } template <> int countl_zero(ull x) { return __builtin_clzll(x); }
template <typename T> int countr_zero(T x); template <> int countr_zero(uint x) { return __builtin_ctz(x); } template <> int countr_zero(ull x) { return __builtin_ctzll(x); }
template <typename T> int bit_width(T x) { return numeric_limits<T>::digits - countl_zero(x); }
#endif

template <typename T> int sgn(T x) { return (T(0) < x) - (x < T(0)); }
template <typename T> T randint(T l, T r) { return uniform_int_distribution<T>(l, r)(rng); }
template <typename T> T randf(T l, T r) { return uniform_real_distribution<T>(l, r)(rng); }
template <typename T> int log2if(T x) { return bit_width(x + 0ULL) - 1; }
template <typename T> int log2ic(T x) { return bit_width(x - 1ULL); }
bool inside(int x, int y, int n, int m) { return x >= 0 && x < n && y >= 0 && y < m; }
ll sqdist(const pair<int, int> &p, const pair<int, int> &q) { ll x = p.first - q.first, y = p.second - q.second; return x * x + y * y; }

template <typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<>>;
template <typename T, typename Comp = less<>> using ordered_set = tree<T, null_type, Comp, rb_tree_tag, tree_order_statistics_node_update>;
template <typename T = null_type> using pref_trie = trie<string, T, trie_string_access_traits<>, pat_trie_tag, trie_prefix_search_node_update>;

#if __cplusplus >= 201703L
template <typename, typename = void> struct is_iterable : false_type {};
template <typename T> struct is_iterable<T, void_t<decltype(declval<T>().begin()), decltype(declval<T>().end())>> : true_type {};
template <> struct is_iterable<string> : false_type {};
template <typename T> constexpr bool is_iterable_v = is_iterable<T>::value;
template <typename T, typename V = enable_if_t<is_iterable_v<T>, typename T::value_type>> ostream &operator<<(ostream &os, const T &t) { for (const V &v : t) os << v << ' '; return os; }
template <typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &p) { return os << '(' << p.first << ' ' << p.second << ')'; }
void dbg_header_(const char *f, int l, const char *e) { cout << "\033[35m(" << f << ':' << l << ") \033[1m" << e << ":\033[0m "; }
template <typename T, typename = enable_if_t<!is_iterable_v<T>>> void dbg_(const T &t, const char *f, int l, const char *e) { dbg_header_(f, l, e); cout << "\033[33;1m" << t << "\033[0m" << endl; }
template <typename T, typename V = enable_if_t<is_iterable_v<T> && !is_iterable_v<typename T::value_type>, typename T::value_type>, typename = void> void dbg_(const T &t, const char *f, int l, const char *e) { dbg_header_(f, l, e); cout << "\033[33;1m"; for (const V &v : t) cout << v << ' '; cout << "\033[0m" << endl; }
template <typename T, typename = enable_if_t<is_iterable_v<T> && is_iterable_v<typename T::value_type>, typename T::value_type>, typename = void, typename = void> void dbg_(const T &t, const char *f, int l, const char *e) { dbg_header_(f, l, e); cout << '\n'; for (int i = 0; i < t.size(); i++) cout << "\033[36m" << i << ":\033[33;1m " << t[i] << "\033[0m" << endl; }
#ifdef DEBUG
#define dbg(t) dbg_((t), __func__, __LINE__, #t)
#else
#define dbg(t)
#endif
#endif
// clang-format on

constexpr ull M = (1ULL << 61) - 1;

ull mul(ull a, ull b)
{
    ull l1 = uint(a), h1 = a >> 32, l2 = uint(b), h2 = b >> 32;
    ull l = l1 * l2, m = l1 * h2 + l2 * h1, h = h1 * h2;
    ull ans = (l & M) + (l >> 61) + (h << 3) + (m >> 29) + (m << 35 >> 3) + 1;
    ans = (ans & M) + (ans >> 61);
    ans = (ans & M) + (ans >> 61);
    return ans - 1;
}

ull pow(ull n, ull p, ull m)
{
    ull ans = 1;
    while (p > 0)
    {
        if (p & 1)
            ans = ans * n % m;
        n = n * n % m;
        p >>= 1;
    }
    return ans;
}

void solve()
{
#ifdef DEBUG
    cout << "\033[31;1m======================================================================\033[0m" << endl;
#endif
    int m, n, k;
    cin >> m >> n >> k;
    vector<string> grid(m);
    for (string &s : grid)
        cin >> s;
    int log = log2if(k);
    ull base = randint<ull>(69ULL, 696969696969ULL);
    vector dp(log + 1, vector(m, vector(n, vector<ull>(8))));
    for (int i = 0; i < m; i++)
    {
        for (int j = 0; j < n; j++)
        {
            for (int d = 0; d < 8; d++)
                dp[0][i][j][d] = grid[i][j];
        }
    }
    for (int l = 1; l <= log; l++)
    {
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
            {
                for (int d = 0; d < 8; d++)
                {
                    int amt = 1 << l - 1;
                    int ni = ((i + dx[d] * amt) % m + m) % m, nj = ((j + dy[d] * amt) % n + n) % n;
                    dp[l][i][j][d] = (dp[l - 1][i][j][d] + mul(pow(base, amt, M), dp[l - 1][ni][nj][d])) % M;
                }
            }
        }
    }
    map<ull, int> freq;
    for (int i = 0; i < m; i++)
    {
        for (int j = 0; j < n; j++)
        {
            for (int d = 0; d < 8; d++)
            {
                int amt = 0;
                ull h = 0;
                for (int l = 0; l <= log; l++)
                {
                    if (!(k & 1 << l))
                        continue;
                    int ni = ((i + dx[d] * amt) % m + m) % m, nj = ((j + dy[d] * amt) % n + n) % n;
                    h = (h + mul(pow(base, amt, M), dp[l][ni][nj][d])) % M;
                    amt += 1 << l;
                }
                freq[h]++;
            }
        }
    }
    ll ways = 0;
    for (int c : freq | views::values)
        ways += ll(c) * c;
    ll denom = m * n * 8;
    denom *= denom;
    ll g = gcd(ways, denom);
    ways /= g;
    denom /= g;
    cout << ways << '/' << denom << endl;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    // cin >> t;
    while (t--)
        solve();
}

• Subtask 1: 140 / 160