// Author: Damian Straszak

import java.io.*;
import java.util.*;

public class E
{
	BufferedReader br;
	PrintWriter out;
	StringTokenizer st;
	boolean eof;
	public static final int INF=(1<<29);
	int[] ispower;
	int[] possible;
	
	int get_next_left(int old,int x,int oldsum)
	{
		int a=old,b=oldsum-a;
		if (a%x==0) a+=x;
		else return -1;
		if (ispower[a]!=-1)
		{
			if (2*a>b) 
			{
				b+=a;
				a=0;
			}
		}
		return a;
	}

	int get_next_right(int old,int x,int oldsum)
	{
		int a=old,b=oldsum-a;
		if (b%x==0) b+=x;
		else return -1;
		if (ispower[b]!=-1)
		{
			if (2*b>a) 
			{
				a+=b;
				b=0;
			}
		}
		return a;
	}


	void solve() throws IOException 
	{
		ispower=new int[1<<18];
		possible=new int[1<<18];
		for(int i=0;i<(1<<18);i++) ispower[i]=-1;
		for(int i=0;i<18;i++) ispower[1<<i]=i;
		int test=nextInt();
		while(test-->0)
		{
			int n=nextInt();
			int sum=0;
			int[] num=new int[n];
			for(int i=0;i<n;i++) 
			{
				num[i]=nextInt();
				sum+=num[i];
			}
			if (ispower[sum]==-1) {out.println("no");continue;}
			int[][] v = new int[n+1][];
			int[] len = new int[n+1];
			v[0]=new int[1];
			v[0][0]=0;
			len[0]=1;
			sum=0;
			for(int i=1;i<=n;i++)
			{
				int x=num[i-1];
				ArrayList<Integer> pos=new ArrayList<Integer>();
				for(int j=0;j<len[i-1];j++)
				{
					int y=v[i-1][j];
					int yn[]={get_next_right(y,x,sum),get_next_left(y,x,sum)};
					for(int k=0;k<2;k++)
					{
						if (yn[k]>=0 && possible[yn[k]]==0)
						{
							possible[yn[k]]=1;
							pos.add(yn[k]);
						}
					}
				}
				len[i]=pos.size();
				v[i]=new int[len[i]];
				for(int j=0;j<len[i];j++) v[i][j]=pos.get(j);
				for(int j=0;j<pos.size();j++) possible[pos.get(j)]=0;
				sum+=x;
			}
			
			
			int b=-1;
			for(int i=0;i<len[n];i++) if (v[n][i]==0 || v[n][i]==sum) b=i;
			if (b<0) {out.println("no");continue;}
			String s = new String();
			for(int i=n-1;i>=0;i--)
			{
				int akt=v[i+1][b];
				sum-=num[i];
				for(int j=0;j<len[i];j++)
				{
					if (get_next_left(v[i][j],num[i],sum)==akt) {b=j;s+="l";break;}
					if (get_next_right(v[i][j],num[i],sum)==akt) {b=j;s+="r";break;}
				}
			}
			for(int i=n-1;i>=0;i--) out.print(s.charAt(i));
			out.println("");
		}
		
	}

	E() throws IOException 
	{
		br=new BufferedReader(new InputStreamReader(System.in));
		out=new PrintWriter(System.out);
		solve();
		out.close();
	}

	public static void main(String[] args) throws IOException 
	{
		new E();
	}

	String nextToken() 
	{
		while (st==null || !st.hasMoreTokens()) 
		{
			try 
			{
				st=new StringTokenizer(br.readLine());
			} 
			catch (Exception e) 
			{
				eof=true;
				return null;
			}
		}
		return st.nextToken();
	}

	String nextString() 
	{
		try 
		{
			return br.readLine();
		} 
		catch (IOException e) 
		{
			eof=true;
			return null;
		}
	}

	int nextInt() throws IOException 
	{
		return Integer.parseInt(nextToken());
	}

	long nextLong() throws IOException 
	{
		return Long.parseLong(nextToken());
	}

	double nextDouble() throws IOException 
	{
		return Double.parseDouble(nextToken());
	}
	
}