Submission #1114718

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114718		Dan4Life	Snake Escaping (JOI18_snake_escaping)	C++17	22 / 100	623 ms	65024 KiB

snake_escaping

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a),end(a)

string s;
int n, l, q;
const int p3[] = {1,3,9,27,81,243,729};
const int B1 = 5;
const int B2 = 20-B1;
const int N = p3[B1];
int pre[N][1<<B2], score[N][1<<B2];

int calc(string lol){
	int p = 1, ans = 0, xd;
	for(int i = 0; i < B1; i++){
		if(lol[i]=='?') xd=2;
		else xd = lol[i]-'0';
		ans+=xd*p, p*=3;
	}
	return ans;
}

int calc(int lol){
	int p = 1, ans = 0;
	for(int i = 0; i < B1; i++)
		ans+=(lol>>i&1)*p, p*=3;
	return ans;
}

int32_t main(){
	ios_base::sync_with_stdio(false); cin.tie(0);
	cin >> l >> q >> s; n = (1<<l);
	if(l<=B1){
		for(int _ = 0; _ < q; _++){
			string t; cin >> t; 
			reverse(all(t));
			int cnt = 0;
			for(int i = 0; i < n; i++){
				int ok = 1;
				for(int j = 0; j < l; j++) 
					ok&=(t[j]=='?' or (t[j]-'0')==(i>>j&1));
				cnt+=ok*(s[i]-'0');
			}
			cout << cnt << "\n";
		}
		return 0;
	}
	l-=B1;
	for(int mask = 0; mask < n; mask++){
		int mask1 = calc(mask&((1<<B1)-1));
		int mask2 = mask>>B1;
		int sc = s[mask]-'0';
		score[mask1][mask2]+=sc;
		for(int t = mask2; ; t--,t&=mask2){
			pre[mask1][t]+=sc; if(!t) break;
		}
	}
	for(int mask = 0; mask < (1<<(B1*2)); mask++){
		string t = "", t2 = "";
		for(int i = 0; i < B1*2; i+=2){
			int cur = mask>>i&1;
			t+=(char)(cur+'0');
			if(mask>>(i+1)&1) cur=2;
			t2+=(char)(cur+'0');
		}
		int mask1 = calc(t);
		int mask2 = calc(t2);
		if(t==t2) continue;
		for(int i = 0; i < (1<<l); i++){
			pre[mask2][i]+=pre[mask1][i];
			score[mask2][i]+=score[mask1][i];
		}
	}
	for(int _ = 0; _ < q; _++){
		string t; cin >> t; reverse(all(t));
		int x = calc(t.substr(0,B1));
		t = t.substr(B1);
		int cnt = 0, ans = 0, xd2 = 0; 
		vector<int> pos, pos2; 
		pos.clear(); pos2.clear();
		for(int i = 0; i < sz(t); i++){
			if(t[i]=='?') pos.pb(i),cnt++;
			else{
				pos2.pb(i);
				if(t[i]=='1') xd2+=1<<i;
			}
		}
		if(cnt*2<=B2){
			for(int mask = 0; mask < (1<<cnt); mask++){
				int xd = 0;
				for(int i = 0; i < cnt; i++)
					if(mask>>i&1) xd+=1<<pos[i];
				ans+=score[x][xd+xd2];
			}
		}
		else{
			cnt = sz(pos2); ans = pre[x][0];
			for(int mask = 1; mask < (1<<cnt); mask++){
				int num = __builtin_popcount(mask), xd=0;
				for(int i = 0; i < cnt; i++)
					if(mask>>i&1) xd+=(1<<pos2[i])*(t[pos2[i]]=='0');
				ans+=(num%2?-1:1)*score[x][xd];
			}
		}
		cout << ans << "\n";
	}
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 10 / 10
• Subtask 4: 0 / 53
• Subtask 5: 0 / 25