1+ import java .io .*;
2+ import java .util .*;
3+ 4+ class RatInAMaze {
5+ static BufferedReader br ;
6+ static StringTokenizer st ;
7+ 8+ static int nextInt () throws IOException {
9+ return Integer .parseInt (next ());
10+ }
11+ 12+ static String next () throws IOException {
13+ while (st == null || !st .hasMoreTokens ()) {
14+ st = new StringTokenizer (br .readLine ());
15+ }
16+ return st .nextToken ();
17+ }
18+ 19+ static long nextLong () throws IOException {
20+ return Long .parseLong (next ());
21+ }
22+ 23+ public static void main (String args []) throws IOException {
24+ br = new BufferedReader (new InputStreamReader (System .in ));
25+ int t = nextInt ();
26+ while (t -- > 0 ) {
27+ input ();
28+ }
29+ br .close ();
30+ }
31+ 32+ public static void input () throws IOException {
33+ int n = nextInt ();
34+ int m [][] = new int [n ][n ];
35+ boolean vis [][] = new boolean [n ][n ];
36+ // {1, 0, 0, 0},
37+ // {1, 1, 0, 1},
38+ // {1, 1, 0, 0},
39+ // {0, 1, 1, 1}
40+ for (int i = 0 ; i < n ; i ++) {
41+ for (int j = 0 ; j < n ; j ++) {
42+ m [i ][j ] = nextInt ();
43+ }
44+ }
45+ 46+ if (m [0 ][0 ] == 1 ) {
47+ vis [0 ][0 ] = true ;
48+ System .out .println (findPath (m , n , vis ));
49+ }
50+ }
51+ 52+ static ArrayList <String > findPath (int [][] m , int n , boolean [][] vis ) {
53+ String pos = "" ;
54+ ArrayList <String > ans = new ArrayList <>();
55+ 56+ dfs (pos , 0 , 0 , m , ans , vis , n );
57+ 58+ return ans ;
59+ 60+ }
61+ 62+ static void dfs (String pos , int row , int col , int [][] m , ArrayList <String > ans , boolean [][] vis ,
63+ int n ) {
64+ 65+ if (col == n - 1 && row == n - 1 ) {
66+ ans .add (pos .toString ());
67+ return ;
68+ }
69+ if (row < n - 1 && m [row + 1 ][col ] == 1 && vis [row + 1 ][col ] == false ) {
70+ 71+ vis [row ][col ] = true ;
72+ dfs (pos + "D" , row + 1 , col , m , ans , vis , n );
73+ vis [row ][col ] = false ;
74+ 75+ }
76+ if (col > 0 && m [row ][col - 1 ] == 1 && vis [row ][col - 1 ] == false ) {
77+ 78+ vis [row ][col ] = true ;
79+ dfs (pos + "L" , row , col - 1 , m , ans , vis , n );
80+ vis [row ][col ] = false ;
81+ 82+ }
83+ if (col < n - 1 && m [row ][col + 1 ] == 1 && vis [row ][col + 1 ] == false ) {
84+ 85+ vis [row ][col ] = true ;
86+ dfs (pos + "R" , row , col + 1 , m , ans , vis , n );
87+ vis [row ][col ] = false ;
88+ 89+ }
90+ if (row > 0 && m [row - 1 ][col ] == 1 && vis [row - 1 ][col ] == false ) {
91+ 92+ vis [row ][col ] = true ;
93+ dfs (pos + "U" , row - 1 , col , m , ans , vis , n );
94+ vis [row ][col ] = false ;
95+ 96+ }
97+ 98+ }
99+ }
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