Submission #797414

#	Time	Username	Problem	Language	Result	Execution time	Memory
797414		finn__	L-triominoes (CEOI21_ltriominoes)	C++17	0 / 100	675 ms	468 KiB

ltrominoes

#pragma GCC optimize("O3")
#pragma GCC target("avx,avx2,sse4")

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

constexpr size_t W = 13, K = 250;

struct bmatrix
{
    uint64_t mat[1 << W][1 << (W - 6)];

    void mul_vec(uint64_t const v[1 << (W - 6)], uint64_t res[1 << (W - 6)]) const
    {
        memset(res, 0, sizeof res);
        for (size_t i = 0; i < 1U << W; ++i)
            for (size_t j = 0; j < 1U << (W - 6); ++j)
                if (mat[i][j] & v[j])
                {
                    res[i] = 1;
                    break;
                }
    }
};

pair<size_t, size_t> p[K];
bmatrix transitions;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    size_t w, h, k;
    cin >> w >> h >> k;
    assert(h <= 1000);

    for (size_t i = 0; i < k; ++i)
        cin >> p[i].first >> p[i].second, --p[i].first, --p[i].second;

    for (size_t y = 0; y < 1 << w; ++y)
    {
        queue<uint32_t> q;
        q.push(y << W);

        while (!q.empty())
        {
            uint32_t u = q.front();
            q.pop();

            size_t i = u >> W, j = u & ((1 << W) - 1);

            if (i == (1 << w) - 1)
            {
                transitions.mat[j][y] = 1;
                continue;
            }

            for (size_t h = 0; h < w; ++h)
                if (!(i & (1 << h)))
                {
                    if (h && !(j & (1 << h)) && !(j & (1 << (h - 1))))
                    {
                        size_t ni = i ^ (1 << h), nj = j ^ (1 << h) ^ (1 << (h - 1));
                        q.push((ni << W) | nj);
                    }
                    if (h + 1 < w && !(j & (1 << h)) && !(j & (1 << (h + 1))))
                    {
                        size_t ni = i ^ (1 << h), nj = j ^ (1 << h) ^ (1 << (h + 1));
                        q.push((ni << W) | nj);
                    }
                    if (h + 1 < w && !(i & (1 << (h + 1))) && !(j & (1 << h)))
                    {
                        size_t ni = i ^ (1 << h) ^ (1 << (h + 1)), nj = j ^ (1 << h);
                        q.push((ni << W) | nj);
                    }
                    if (h + 1 < w && !(i & (1 << (h + 1))) && !(j & (1 << (h + 1))))
                    {
                        size_t ni = i ^ (1 << h) ^ (1 << (h + 1)), nj = j ^ (1 << (h + 1));
                        q.push((ni << W) | nj);
                    }
                }
        }
    }

    uint64_t *state = (uint64_t *)malloc((1 << (W - 6)) * sizeof *state);
    uint64_t *state2 = (uint64_t *)malloc((1 << (W - 6)) * sizeof *state2);

    sort(p, p + k, [](auto const &a, auto const &b)
         { return a.second < b.second; });
    size_t i = 0, pos = 0;
    if (k && !p[0].second)
    {
        size_t x = 0;
        while (!p[i].second)
            x |= 1 << p[i].first, ++i;
        state[x >> 6] ^= 1 << (x & 63);
    }
    else
        state[0] = 1;

    while (i < k)
    {
        while (pos < p[i].second)
        {
            transitions.mul_vec(state, state2), ++pos;
            swap(state, state2);
        }
        size_t x = 0;
        size_t j = i;
        while (j < k && p[j].second == p[i].second)
            x |= 1 << p[j].first, ++j;
        i = j;

        memset(state2, 0, sizeof state2);
        for (size_t i = 0; i < 1 << w; ++i)
            if (!(i & x) && state[i])
                state2[i ^ x] = 1;
        state = state2;
    }

    while (pos < h - 1)
    {
        transitions.mul_vec(state, state2), ++pos;
        swap(state, state2);
    }

    cout << ((state[((1 << w) - 1) >> 6] & (1 << (((1 << w) - 1) & 63))) ? "YES" : "NO") << '\n';
}

Compilation message (stderr)

ltrominoes.cpp: In member function 'void bmatrix::mul_vec(const uint64_t*, uint64_t*) const':
ltrominoes.cpp:15:31: warning: 'sizeof' on array function parameter 'res' will return size of 'uint64_t*' {aka 'long unsigned int*'} [-Wsizeof-array-argument]
   15 |         memset(res, 0, sizeof res);
      |                               ^~~
ltrominoes.cpp:13:59: note: declared here
   13 |     void mul_vec(uint64_t const v[1 << (W - 6)], uint64_t res[1 << (W - 6)]) const
      |                                                  ~~~~~~~~~^~~~~~~~~~~~~~~~~
ltrominoes.cpp:15:24: warning: argument to 'sizeof' in 'void* memset(void*, int, size_t)' call is the same expression as the destination; did you mean to dereference it? [-Wsizeof-pointer-memaccess]
   15 |         memset(res, 0, sizeof res);
      |                        ^~~~~~~~~~
ltrominoes.cpp: In function 'int main()':
ltrominoes.cpp:41:26: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   41 |     for (size_t y = 0; y < 1 << w; ++y)
      |                        ~~^~~~~~~~
ltrominoes.cpp:53:19: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   53 |             if (i == (1 << w) - 1)
      |                 ~~^~~~~~~~~~~~~~~
ltrominoes.cpp:115:27: warning: argument to 'sizeof' in 'void* memset(void*, int, size_t)' call is the same expression as the destination; did you mean to dereference it? [-Wsizeof-pointer-memaccess]
  115 |         memset(state2, 0, sizeof state2);
      |                           ^~~~~~~~~~~~~
ltrominoes.cpp:116:30: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  116 |         for (size_t i = 0; i < 1 << w; ++i)
      |                            ~~^~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 7
• Subtask 3: 0 / 11
• Subtask 4: 0 / 17
• Subtask 5: 0 / 35
• Subtask 6: 0 / 20