Submission #539019

#	Time	Username	Problem	Language	Result	Execution time	Memory
539019		amunduzbaev	L-triominoes (CEOI21_ltriominoes)	C++17	28 / 100	755 ms	524288 KiB

ltrominoes

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

#define ar array

struct mtx{
	vector<vector<int>> t;
	int n;
	
	mtx (int sz){
		n = sz;
		t.resize(n, vector<int>(n, 0));
	}
	
	mtx operator * (mtx& b){
		mtx c(n);
		for(int i=0;i<n;i++){
			for(int j=0;j<n;j++){
				for(int k=0;k<n;k++){
					c.t[i][j] |= (t[i][k] & b.t[k][j]);
				}
			}
		} return c;
	}
};

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	int n, m, k; cin>>n>>m>>k;
	vector<ar<int, 2>> a(k);
	for(int i=0;i<k;i++){
		cin>>a[i][0]>>a[i][1];
		a[i][0]--, a[i][1]--;
	}
	
	vector<mtx> pw(30, mtx(1 << n));
	{
		mtx dp(1 << n);
		for(int i=0;i < (1 << n);i++){
			for(int j=0;j < (1 << (n + n));j++){
				int mask = 0, mm = i;
				for(int l=0;l<n;l++){
					if(mm >> l & 1) continue;
					int v = (j >> (2 * l)) & 3;
					if(v == 0){
						if(l + 1 < n && !(mm >> (l + 1) & 1) && !(mask >> (l + 1) & 1)){
							mm |= (1 << l);
							mm |= (1 << (l + 1));
							mask |= (1 << (l + 1));
						}
					}
					if(v == 1){
						if(l + 1 < n && !(mm >> (l + 1) & 1) && !(mask >> l & 1)){
							mm |= (1 << l);
							mm |= (1 << (l + 1));
							mask |= (1 << l);
						}
					}
					if(v == 2){
						if(l && !(mask >> (l - 1) & 1) && !(mask >> l & 1)){
							mm |= (1 << l);
							mask |= (1 << l);
							mask |= (1 << (l - 1));
						}
					}
					if(v == 3){
						if(l + 1 < n && !(mask >> (l + 1) & 1) && !(mask >> l & 1)){
							mm |= (1 << l);
							mask |= (1 << l);
							mask |= (1 << (l + 1));
						}
					}
				}
				
				if(mm == (1 << n) - 1 && !dp.t[i][mask]){
					//~ for(int j=0;j<n;j++) cout<<(i >> j & 1);
					//~ cout<<endl;
					//~ for(int j=0;j<n;j++) cout<<(mask >> j & 1);
					//~ cout<<endl<<endl;
					dp.t[i][mask] = 1;
				}
			}
		}
		
		pw[0] = dp;
		for(int j=1;j<30;j++){
			pw[j] = pw[j-1] * pw[j-1];
		}
	}
	
	sort(a.begin(), a.end(), [&](auto& a, auto& b){
		return (a[1] < b[1]);
	});
	
	vector<int> dp(1 << n);
	dp[(1 << n) - 1] = 1;
	int last = -1;
	for(int i=0;i<k;){
		int j = i, rev = 0;
		while(j<k && a[j][1] == a[i][1]) rev |= (1 << a[j][0]), j++;
		
		int d = a[i][1] - last;
		//~ cout<<d<<endl;
		//~ for(int i=0;i<n;i++) cout<<(rev >> i & 1);
		//~ cout<<endl;
		for(int l=29;~l;l--){
			if(d >> l & 1){
				d ^= (1 << l);
				vector<int> tp(1 << n);
				for(int mask=0;mask < (1 << n);mask++){
					for(int j=0;j < (1 << n);j++){
						if(d){
							tp[j] |= (dp[mask] & pw[l].t[mask][j]);
						} else {
							if(j & rev) continue;
							//~ if(dp[mask] && pw[l].t[mask][j]){
								//~ for(int i=0;i<n;i++) cout<<(mask >> i & 1);
								//~ cout<<endl;
								//~ for(int i=0;i<n;i++) cout<<(j >> i & 1);
								//~ cout<<endl;
							//~ }
							tp[j | rev] |= (dp[mask] & pw[l].t[mask][j]);
						}
					}
				}
				swap(tp, dp);
			}
		} last = a[i][1], i = j;
	}
	
	int d = m - last - 1;
	for(int l=29;~l;l--){
		if(d >> l & 1){
			vector<int> tp(1 << n);
			for(int mask=0;mask < (1 << n);mask++){
				for(int j=0;j < (1 << n);j++){
					tp[j] |= dp[mask] & pw[l].t[mask][j];
				}
			}
			
			swap(tp, dp);
		}
	}
	
	if(dp[(1 << n) - 1]) cout<<"YES\n";
	else cout<<"NO\n";
}

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