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Submission #797202

# Submission time Handle Problem Language Result Execution time Memory
797202 2023-07-29T07:56:45 Z finn__ L-triominoes (CEOI21_ltriominoes) C++17
0 / 100
 120 ms 596 KB 
#include <bits/stdc++.h>
using namespace std;

constexpr size_t W = 6, K = 250;

struct bmatrix
{
    bitset<1 << W> mat[1 << W];

    bmatrix transpose() const
    {
        bmatrix res;
        for (size_t i = 0; i < 1 << W; ++i)
            for (size_t j = 0; j < 1 << W; ++j)
                res.mat[i][j] = mat[j][i];
        return res;
    }

    bmatrix operator*(bmatrix const &y) const
    {
        bmatrix x = y.transpose();
        bmatrix res;

        for (size_t i = 0; i < 1 << W; ++i)
            for (size_t j = 0; j < 1 << W; ++j)
                res.mat[i][j] = (mat[i] & x.mat[j]).any();

        return res;
    }

    bmatrix pow(size_t n) const
    {
        bmatrix a = *this;
        bmatrix res;
        for (size_t i = 0; i < 1 << W; ++i)
            res.mat[i][i] = 1;

        while (n)
        {
            if (n & 1)
                res = res * a;
            a = a * a;
            n >>= 1;
        }

        return res;
    }

    bitset<1 << W> mul_vec(bitset<1 << W> const &v) const
    {
        bitset<1 << W> res;
        for (size_t i = 0; i < 1 << W; ++i)
            res[i] = (mat[i] & v).any();
        return res;
    }
};

void find_transitions(size_t p, size_t q, size_t i, size_t r, size_t s, size_t w, bmatrix &transitions)
{
    if (p == (1 << w) - 1)
    {
        transitions.mat[s][r] = 1;
    }

    if (!(p & (1 << i)))
    {
        // try all 4 possibilities to place a triomino
    }
    else
    {
        // skip
    }
}

pair<size_t, size_t> p[K];
bitset<1 << W> f[1 << W];
vector<uint32_t> pre[1 << W][1 << W];
bitset<1 << (W << 1)> visited;

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

    size_t w, h, k;
    cin >> w >> h >> k;

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

    for (size_t i = 0; i < 1 << w; ++i)
        f[i][0] = 1;
    for (size_t i = 0; i < 1 << w; ++i)
        for (size_t j = 0; j < 1 << w; ++j)
            if (f[i][j])
                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));
                            f[ni][nj] = 1;
                            pre[ni][nj].push_back((i << W) | j);
                        }
                        if (h + 1 < w && !(j & (1 << h)) && !(j & (1 << (h + 1))))
                        {
                            size_t ni = i ^ (1 << h), nj = j ^ (1 << h) ^ (1 << (h + 1));
                            f[ni][j] = 1;
                            pre[ni][nj].push_back((i << W) | j);
                        }
                        if (h + 1 < w && !(i & (1 << (h + 1))) && !(j & (1 << h)))
                        {
                            size_t ni = i ^ (1 << h) ^ (1 << (h + 1)), nj = j ^ (1 << h);
                            f[ni][nj] = 1;
                            pre[ni][nj].push_back((i << W) | j);
                        }
                        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));
                            f[ni][nj] = 1;
                            pre[ni][nj].push_back((i << W) | j);
                        }
                    }

    bmatrix transitions;
    for (size_t i = 0; i < 1 << w; ++i)
    {
        queue<uint32_t> q;
        q.push((((1 << w) - 1) << W) | i);
        visited.reset();

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

            if (!(u & ((1 << W) - 1)))
            {
                transitions.mat[i][u >> W] = 1;
            }

            for (auto const &v : pre[u >> W][u & ((1 << W) - 1)])
                if (!visited[v])
                {
                    q.push(v);
                }
        }
    }

    sort(p, p + k, [](auto const &a, auto const &b)
         { return a.second < b.second; });
    bitset<1 << W> state, state2;
    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] = 1;
    }
    else
        state[0] = 1;

    while (i < k)
    {
        state = transitions.pow(p[i].second - pos).mul_vec(state);
        pos = p[i].second;
        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;

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

    if (pos != h - 1)
    {
        state = transitions.pow(h - 1 - pos).mul_vec(state);
    }

    cout << (state.any() ? "YES" : "NO") << '\n';
}

Compilation message

ltrominoes.cpp: In function 'void find_transitions(size_t, size_t, size_t, size_t, size_t, size_t, bmatrix&)':
ltrominoes.cpp:60:11: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   60 |     if (p == (1 << w) - 1)
      |         ~~^~~~~~~~~~~~~~~
ltrominoes.cpp: In function 'int main()':
ltrominoes.cpp:91:26: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   91 |     for (size_t i = 0; i < 1 << w; ++i)
      |                        ~~^~~~~~~~
ltrominoes.cpp:93:26: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   93 |     for (size_t i = 0; i < 1 << w; ++i)
      |                        ~~^~~~~~~~
ltrominoes.cpp:94:30: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   94 |         for (size_t j = 0; j < 1 << w; ++j)
      |                            ~~^~~~~~~~
ltrominoes.cpp:126:26: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  126 |     for (size_t i = 0; i < 1 << w; ++i)
      |                        ~~^~~~~~~~
ltrominoes.cpp:175:30: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  175 |         for (size_t i = 0; i < 1 << w; ++i)
      |                            ~~^~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 420 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 8 ms 340 KB Output is correct
5 Correct 7 ms 424 KB Output is correct
6 Correct 8 ms 420 KB Output is correct
7 Runtime error 1 ms 544 KB Execution killed with signal 11
8 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Runtime error 1 ms 596 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #3
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 340 KB Output is correct
2 Correct 2 ms 340 KB Output is correct
3 Incorrect 1 ms 420 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #4
0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 424 KB Output is correct
2 Correct 11 ms 424 KB Output is correct
3 Correct 58 ms 412 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 424 KB Output is correct
8 Correct 1 ms 420 KB Output is correct
9 Correct 2 ms 340 KB Output is correct
10 Correct 74 ms 416 KB Output is correct
11 Correct 101 ms 340 KB Output is correct
12 Correct 120 ms 436 KB Output is correct
13 Correct 71 ms 408 KB Output is correct
14 Correct 66 ms 412 KB Output is correct
15 Correct 76 ms 416 KB Output is correct
16 Correct 48 ms 436 KB Output is correct
17 Correct 70 ms 420 KB Output is correct
18 Correct 77 ms 416 KB Output is correct
19 Correct 60 ms 436 KB Output is correct
20 Correct 24 ms 416 KB Output is correct
21 Correct 20 ms 340 KB Output is correct
22 Incorrect 22 ms 440 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #5
0 / 35.0

# Verdict Execution time Memory Grader output
1 Runtime error 2 ms 544 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #6
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 420 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 8 ms 340 KB Output is correct
5 Correct 7 ms 424 KB Output is correct
6 Correct 8 ms 420 KB Output is correct
7 Runtime error 1 ms 544 KB Execution killed with signal 11
8 Halted 0 ms 0 KB -