input:

500
6 20
1 2
1 3
3 4
2 5
3 6
1 6 6 5
2 1 6 2
5 1 2 6
2 6 1 2
6 3 6 4
4 1 1 3
5 6 3 4
2 1 3 5
2 4 1 2
6 2 1 2
6 2 1 4
1 6 1 6
2 5 2 6
2 5 6 2
5 2 1 3
5 6 6 4
4 1 4 5
5 4 4 1
3 6 1 2
6 1 4 3
71 30
1 2
2 3
2 4
4 5
2 6
6 7
4 8
2 9
1 10
9 11
3 12
5 13
5 14
10 15
6 16
13 17
17 18
4 19
5 20
17 21
20 22
4 2...

output:

3
-1
-1
-1
6
3
-1
1
-1
2
3
1
2
-1
-1
6
4
1
-1
3
-1
11
2
-1
5
-1
17
-1
-1
5
-1
2
-1
0
-1
-1
14
53
5
7
-1
-1
2
4
-1
-1
-1
-1
-1
-1
-1
5
-1
5
5
1
-1
-1
-1
-1
5
-1
1
1
-1
1
-1
-1
-1
-1
7
4
-1
9
5
49
-1
-1
-1
19
-1
-1
9
5
-1
-1
5
-1
-1
32
-1
1
49
7
-1
-1
1
-1
-1
-1
8
-1
13
-1
-1
5
7
5
5
-1
-1
-1
-1
-1
-1...

result:

wrong answer 10th lines differ - expected: '1', found: '2'