Submission #498968

#	Time	Username	Problem	Language	Result	Execution time	Memory
498968		inksamurai	Drvca (COCI19_drvca)	C++17	110 / 110	27 ms	3416 KiB

drvca

#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
#define rep(i,n) for(int i=0;i<n;i++)
#define crep(i,x,n) for(int i=x;i<n;i++)
#define drep(i,n) for(int i=n-1;i>=0;i--)
#define vec(...) vector<__VA_ARGS__>
#define _3qplfh5 ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
using pii=pair<int,int>;
using vi=vector<int>;
using vll=vector<long long>;

int main(){
_3qplfh5;
	int n;
	cin>>n;
	vi a(n);
	rep(i,n){
		cin>>a[i];
	}
	sort(all(a));

	vi wata(n,-1);
	wata[n-1]=-1;
	wata[n-2]=-1;
	drep(i,n-2){
		if(a[i+1]-a[i]!=a[i+2]-a[i+1]){
			break;
		}
		wata[i]=a[i+1]-a[i];
	}
	// rep(i,n){
	// 	cout<<wata[i]<<" ";
	// }
	// cout<<"\n";

	auto g=[&](vi up,vi dw){
		vec(vi) cands;
		cands.pb(up);
		cands.pb(dw);
		int now=0;
		rep(t,2){
			if(!sz(cands[t]))
				return;
			now+=sz(cands[t]);
		}
		if(now!=n){
			return;
		}
		rep(t,2){
			crep(i,2,sz(cands[t])){
				if(cands[t][i]-cands[t][i-1]!=cands[t][i-1]-cands[t][i-2])
					return;
			}
		}
		rep(t,2){
			cout<<sz(cands[t])<<"\n";
			for(auto x : cands[t]){
				cout<<x<<" ";
			}
			cout<<"\n";
		}
		exit(0);
	};
	
	auto f=[&](int id,int id2){
		vi up,dw;
		up.pb(a[id]);
		up.pb(a[id2]);
		int diff=a[id2]-a[id];
		rep(i,n){
			if(i==id or i==id2){
				continue;
			}
			if(sz(dw)>=3){
				if(dw[sz(dw)-1]-dw[sz(dw)-2]!=dw[sz(dw)-2]-dw[sz(dw)-3]){
					return;
				}
			}
			int x=a[i];
			if(x-up.back()!=diff){
				dw.pb(x);
			}else{
				if(i>=n-3 or wata[i+1]!=-1){
					if(sz(dw)<=1 or i>=n-3 or a[i]-dw[sz(dw)-1]==dw[sz(dw)-1]-dw[sz(dw)-2]){
						crep(j,i,n){
							dw.pb(a[j]);
						}
						g(up,dw);
						crep(j,i,n){
							dw.pop_back();
						}
					}
				}
				up.pb(x);
			}
		}
		g(up,dw);
	};
	if(n!=2){
		f(0,1);
		f(0,2);
		f(1,2);
	}else{
		g({a[0]},{a[1]});
	}
	cout<<"-1\n";
//	
	return 0;
}

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