#include<bits/stdc++.h>
using namespace std;
int n,cum,b[200001],cmp=2;
struct lode
{
	int x,cnt;
} a[200001];
int main()
{
	cin>>n;
    for(int i=1; i<=n; i++)
    {
    	cin>>a[i].x;
		a[i].cnt=i;
	}
	b[1]=a[1].cnt;
	a[1].x=-1;
	while(cum<n)
	{
		for(int i=2; i<=n; i++)
		{
			if(a[i-1].x!=a[i].x&&a[i].x!=-1&&a[i-1].x!=-1)
			{
				b[cmp]=a[i].cnt;
				cum++;
				a[i].x=-1;
				cmp++;
			}
		}
		for(int i=1; i<cmp; i++)
		{
			cout<<b[i]<<" ";
			b[i]=0;
		}
		cmp=1;
		cout<<endl;
	}
    return 0;
}