Submission #444742

#	Time	Username	Problem	Language	Result	Execution time	Memory
444742		penguinhacker	Drvca (COCI19_drvca)	C++14	110 / 110	135 ms	3152 KiB

drvca

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

#define ll long long
#define ar array

const int mxN=1e5;
int n, a[mxN], prv[mxN], nxt[mxN], cnt;
vector<int> cur={0};
bool rem[mxN]={1}, bad[mxN];

void calc(int i) {
	if (i==-1)
		return;
	cnt-=bad[i];
	if (rem[i])
		bad[i]=0;
	else {
		if (prv[i]==-1||nxt[i]==-1)
			bad[i]=0;
		else {
			assert(!rem[prv[i]]&&!rem[nxt[i]]);
			bad[i]=a[i]-a[prv[i]]!=a[nxt[i]]-a[i];
		}
	}
	cnt+=bad[i];
}

void ck() {
	if (cnt)
		return;
	assert(cnt==0&&cur.size()&&n-cur.size()>0);
	vector<bool> other(n, 1);
	cout << cur.size() << "\n";
	for (int i : cur) {
		other[i]=0;
		cout << a[i] << " ";
	}
	cout << "\n" << n-cur.size() << "\n";
	for (int i=0; i<n; ++i)
		if (other[i])
			cout << a[i] << " ";
	exit(0);
}

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	for (int i=0; i<n; ++i)
		cin >> a[i];
	sort(a, a+n);
	for (int i=1; i<n; ++i) {
		prv[i]=i-1;
		nxt[i]=i+1;
	}
	prv[1]=-1, nxt[n-1]=-1;
	for (int i=1; i<n; ++i)
		calc(i);
	ck();
	for (int i=1; i<n; ++i) {
		int d=a[i]-a[0];
		for (int j=i; j<n;) {
			assert(!rem[j]);
			cur.push_back(j);
			nxt[prv[j]]=nxt[j], prv[nxt[j]]=prv[j], rem[j]=1;
			calc(j), calc(prv[j]), calc(nxt[j]);
			ck();
			int p=lower_bound(a, a+n, a[j]+d)-a;
			p=max(j+1, p);
			if (p==n||a[p]!=a[j]+d)
				break;
			j=p;
		}
		while(cur.size()>1) {
			int j=cur.back();
			cur.pop_back();
			nxt[prv[j]]=j, prv[nxt[j]]=j, rem[j]=0;
			calc(j), calc(prv[j]), calc(nxt[j]);
		}
	}
	cout << -1;
	return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 30 / 30
• Subtask 4: 30 / 30