// fruit
#include <bits/stdc++.h>
#define var long long
using namespace std;

int main()
{
	freopen("fruit.in", "r", stdin);
	freopen("fruit.out", "w", stdout);
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	var n; cin>>n;
	var a[n];
	for(var i=0; i<n; i++)
		cin>>a[i];
	while(1)
	{
		var prev=-1;
		bool f=1;
		for(var i=0; i<n; i++)
			if(a[i]!=-1)
			{
				if(a[i]!=prev)
				{
					if(f)
						cout<<i+1, f=0;
					else
						cout<<" "<<i+1;
					prev=a[i];
					a[i]=-1;
				}
			}
		if(prev==-1)
			break;
		cout<<endl;
	}

    return 0;
}