Submission #753921

#	Time	Username	Problem	Language	Result	Execution time	Memory
753921		lohacho	L-triominoes (CEOI21_ltriominoes)	C++14	100 / 100	562 ms	97836 KiB

ltrominoes

#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#define mi(x, y) (x = min(x, y))
#define ma(x, y) (x = max(x, y))
using namespace std;
 
const int NS = 13;
int way[(1 << NS) + 4][(1 << NS) + 4];
vector<int> vway[(1 << NS) + 4];
int dist[(1 << NS) + 4];
 
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
 
    int w, h, k;
    cin >> w >> h >> k;
    vector<pair<int, int>> a(k);
    for(int i = 0; i < k; ++i){
        cin >> a[i].first >> a[i].second;
        swap(a[i].first, a[i].second);
        --a[i].first, --a[i].second;
    }
    sort(a.begin(), a.end());
 
    for(int i = 0; i < (1 << w); ++i){
        auto dfs = [&](auto&&self, int x, int bt)->void{
            int now = (i >> x & 1);
            if(now){
                self(self, x + 1, bt);
                return;
            }
            if(x == w){
                way[i][bt] = 1;
                return;
            }
            int nxt = (i >> (x + 1) & 1);
            int btnow = (bt >> x & 1);
 
            if(x + 1 < w && !nxt && !btnow){
                self(self, x + 2, bt | 1 << x);
            }
            if(x + 1 < w && !nxt){
                self(self, x + 2, bt | 1 << (x + 1));
            }
            if(x + 1 < w && !btnow){
                self(self, x + 1, bt | 1 << x | 1 << (x + 1));
            }
            if(!btnow && x && !(bt >> (x - 1) & 1)){
                self(self, x + 1, bt | 1 << x | 1 << (x - 1));
            }
        };
        dfs(dfs, 0, 0);
        for(int j = 0; j < (1 << w); ++j){
            if(way[i][j]){
                vway[i].push_back(j);
            }
        }
    }
 
    vector<int> dp(1 << w);
    int p = 0, bt = 0;
    while(p < k && a[p].first == 0){
        bt |= (1 << a[p].second);
        ++p;
    }
    dp[bt] = 1;
    for(int i = 1; i < h; ++i){
        int nxt = h - 1;
        if(p < k) nxt = a[p].first;
        int add = (nxt - 2 - i) / 6;
        if(add > 0) i += add * 6;
        bt = 0;
        while(p < k && a[p].first == i){
            bt |= (1 << a[p].second);
            ++p;
        }
        vector<int> ndp(1 << w);
        for(int j = 0; j < (1 << w); ++j){
            if(!dp[j]) continue;
            for(auto&nxt:vway[j]){
                //cout << i << ' ' << j << ' ' << nxt << ' ' << bt << endl;
                if(!(nxt & bt)){
                    ndp[nxt | bt] = 1;
                }
            }
        }
        swap(dp, ndp);
    }
 
    if(dp[(1 << w) - 1]){
        cout << "YES\n";
    }
    else{
        cout << "NO\n";
    }
    
    return 0;
}

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