Submission #797343

#	Time	Username	Problem	Language	Result	Execution time	Memory
797343		Johann	L-triominoes (CEOI21_ltriominoes)	C++14	10 / 100	8048 ms	524288 KiB

ltrominoes

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

typedef long long ll;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

int W, H, K;
map<int, int> blocked;
vb dp[2];

void dfs(int idx, int base, int next, vb &nextdp)
{
    if (idx == W)
    {
        nextdp[next] = true;
        return;
    }
    if (base & (1 << idx))
        dfs(idx + 1, base, next, nextdp);
    else
    {
        // _X my pos: 1 << idx

        // TT
        // _T
        if (idx < W - 1 && ((3 << idx) & next) == 0)
            dfs(idx + 1, base | (1 << idx), next | (3 << idx), nextdp);

        // _TT
        // _T_
        if (idx > 0 && ((3 << (idx - 1)) & next) == 0)
            dfs(idx + 1, base | (1 << idx), next | (3 << (idx - 1)), nextdp);

        // T_
        // TT
        if (idx < W - 1 && (base & (3 << idx)) == 0 && (next & (2 << idx)) == 0)
            dfs(idx + 2, base | (3 << idx), next | (2 << idx), nextdp);

        // _T
        // TT
        if (idx < W - 1 && (base & (3 << idx)) == 0 && (next & (1 << idx)) == 0)
            dfs(idx + 2, base | (3 << idx), next | (1 << idx), nextdp);
    }
}

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

    cin >> W >> H >> K;
    for (int k = 0, x, y; k < K; ++k)
    {
        cin >> x >> y;
        --x, --y;
        blocked[y] = blocked[y] | (1 << x);
    }

    dp[0] = vb(1 << W, false);
    dp[0][0] = true;
    for (int i = 0; i < H; ++i)
    {
        int ii = i & 1;
        int ni = ii ^ 1;
        dp[ni] = vb(1 << W, false);

        for (int j = 0; j < sz(dp[ii]); ++j)
        {
            if (!dp[ii][j])
                continue;
            if (j & blocked[i])
                continue;

            dfs(0, j | blocked[i], 0, dp[ni]);
        }
    }

    if (dp[H & 1][0])
        cout << "YES\n";
    else
        cout << "NO\n";

    return 0;
}

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