Submission #533463

#	Time	Username	Problem	Language	Result	Execution time	Memory
533463		hhhhaura	Cheerleaders (info1cup20_cheerleaders)	C++14	25 / 100	213 ms	2380 KiB

cheerleaders

#define wiwihorz
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("sse")
#pragma loop-opt(on)
#define rep(i, a, b) for(int i = a; i <= b; i ++)
#define rrep(i, a, b) for(int i = b; i >= a; i--)
#define ceil(a, b) ((a + b - 1) / (b))
#define all(x) x.begin(), x.end()
#define lld long double
#define pii pair<int, int>
#define random mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count())
using namespace std;
#define INF 1000000000
#define MOD 1000000007
#define eps (1e-9)

#ifdef wiwihorz
#define print(a...) cerr<<"Line "<<__LINE__<<":",kout("[" + string(#a) + "] = ", a)
void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L)==R], ++L;}
void kout() { cerr << endl; }
template<class T1, class ... T2> void kout(T1 a, T2 ... e) { cerr << a << " ", kout(e...);} 
#else
#define print(...) 0
#define vprint(...) 0
#endif
#define x first
#define y second
namespace solver {
	int n, tot, mask;
	vector<int> a, b, cnt;
	void init_(int _n) {
		n = _n;
		tot = 1 << n;
		mask = tot - 1;
		a.assign(tot, 0);
		b.assign(tot, 0);
		cnt.assign(tot, 0);
	}
	string get_ans(pii opt) {
		string s = "2";
		rep(i, 1, opt.x) s += "2";
		rep(i, 0, n - 1) {
			if((opt.y >> i) & 1) s += "1";
			if(i != n - 1) s += "2";
		}
		return s;
	}
	void solve() {
		pii opt = {0, 0};
		int ans = INF;
		vector<int> tp(tot, 0);
		rep(i, 0, tot - 1) tp[a[i]] = i;
		a = tp;
		rep(i, 0, n - 1) {
			pii p = {i, 0};
			int best = 0;
			rep(j, 0, tot - 1) b[j] = mask & ((a[j] >> (n - i)) | (a[j] << i));
//			rep(j, 0, tot - 1) print(i, j, bitset<2>(a[j]), bitset<2>(b[j]));
			rep(j, 1, n) {
				int L = 0, R = 0, bot = 1 << (n - j);
				int val = ((1 << j) - 1) << (n - j);
//				print(i, j, bitset<2>(bot), bitset<2>(val));
				cnt.assign(tot, 0);
				rep(k, 0, tot - 1) {
					int cur = b[k] & val;
					int to = cur ^ bot;
					if(cur > to) R += cnt[to];
					else L += cnt[to];
					cnt[cur] ++;
//					print(L, R);
				}
//				print(L, R);
				if(L > R) p.y |= bot;
				best += min(L, R);
			}
//			print(best);
			if(best < ans) opt = p, ans = best;
		}
		cout << ans << "\n";
		cout << get_ans(opt) << "\n";
	}
};
using namespace solver;
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	int n; cin >> n;
	init_(n);
	rep(i, 0, tot - 1) cin >> a[i];
	if(n == 1) cout << "0\n";
	else solve();
	return 0;
}

Compilation message (stderr)

cheerleaders.cpp:5: warning: ignoring '#pragma loop ' [-Wunknown-pragmas]
    5 | #pragma loop-opt(on)
      | 
cheerleaders.cpp:20:13: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   20 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L)==R], ++L;}
      |             ^~~~
cheerleaders.cpp:20:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   20 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L)==R], ++L;}
      |                     ^~~~

• Subtask 1: 0 / 16
• Subtask 2: 5 / 10
• Subtask 3: 20 / 25
• Subtask 4: 0 / 21
• Subtask 5: 0 / 28