#include<bits/stdc++.h>
using namespace std;
const int N=2*1e5+10;
int n,a[N],k;
queue<int> q[N];
template<typename T> void read (T&x)
{
	char c;
	int sign=1;
	x=0;
	do{
		c=getchar();
		if(c=='-') sign=-1;
	}
	while(c>'9'||c<'0');
	do{
		x=x*10+c-'0';
		c=getchar();
	}
	while(isdigit(c));
	x*=sign;
}
int main(){
	read(n);
	for(int i=1;i<=n;i++){
		read(a[i]);
		if(a[i]==a[i-1]){
			q[k].push(i);	
		}
		else{
			k++;
			q[k].push(i);
		}
	}
	while(n!=0){
		for(int i=1;i<=k;i++){
			if(!q[i].empty()){
			cout<<q[i].front()<<" ";
			q[i].pop();
			n--;
			}
		}
		cout<<endl;
	}
	return 0;
}