input:

210
2 1
1 2
10 6
1 2
2 3
4 5
5 6
7 8
8 9
12 9
1 2
2 3
3 4
5 6
6 7
7 8
9 10
10 11
11 12
10 5
1 2
2 3
3 4
4 5
5 6
996 993
2 1
3 2
4 3
5 4
6 5
7 6
8 7
9 8
10 9
11 10
12 11
13 12
14 13
15 14
16 15
17 16
18 17
19 18
20 19
21 20
22 21
23 22
24 23
25 24
26 25
27 26
28 27
29 28
30 29
31 30
32 31
33 32
34 33...

output:

1
2
2
3
3
3
3
2
2
3
4
4
5
5
5
5
2
2
3
4
5
2
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
...

result:

wrong answer 6th lines differ - expected: '4', found: '3'