private void Scan()
{
N = int.Parse(Console.ReadLine());
var line = Console.ReadLine().Split(' ');
Pq = new PQ();
I[] kk = new I[N];
I[] gg = new I[N];
for (int i = 0; i < N; i++)
{
int a = int.Parse(line[i]);
if (i % 2 == 1)
{
kk[i] = new I(a, i);
gg[i] = new I(int.MaxValue, -1);
}
else
{
gg[i] = new I(a, i);
kk[i] = new I(int.MaxValue, -1);
}
}
G = new SegTree(gg);
K = new SegTree(kk);
Pq.Push(new S(0, N, G.Q(0, N)));
}
public void Solve()
{
Scan();
Anser = new int[N];
int cnt = 0;
while (Pq.Length > 0)
{
S top = Pq.Pop();
int left = top.Left;
int right = top.Right;
I min = top.Min;
I rightMin;
if (left % 2 == 0)
{
rightMin = K.Q(min.Index, right);
S a = new S(left, min.Index, G.Q(left, min.Index));
S b = new S(min.Index + 1, rightMin.Index, K.Q((min.Index + 1), rightMin.Index));
S c = new S(rightMin.Index + 1, right, G.Q((rightMin.Index + 1), right));
Pq.Push(a);
Pq.Push(b);
Pq.Push(c);
}
else
{
rightMin = G.Q(min.Index, right);
S a = new S(left, min.Index, K.Q(left, min.Index));
S b = new S(min.Index + 1, rightMin.Index, G.Q((min.Index + 1), rightMin.Index));
S c = new S(rightMin.Index + 1, right, K.Q((rightMin.Index + 1), right));
Pq.Push(a);
Pq.Push(b);
Pq.Push(c);
}
Anser[cnt] = min.Value;
Anser[cnt + 1] = rightMin.Value;
cnt += 2;
}
Console.WriteLine(string.Join(" ", Anser));
}