input:

20 3
1 2
1 3
3 4
4 5
1 6
6 7
1 8
5 9
8 10
5 11
7 12
11 13
12 14
11 15
4 16
7 17
2 18
1 19
3 20
8 20
12 4
10 1

output:

344

result:

wrong answer 1st numbers differ - expected: '307', found: '344'

input:

98765 1
2 1
3 1
4 2
5 2
6 5
7 4
8 6
9 7
10 7
11 6
12 1
13 11
14 13
15 7
16 6
17 14
18 4
19 13
20 14
21 11
22 21
23 1
24 13
25 7
26 16
27 8
28 21
29 20
30 10
31 12
32 10
33 7
34 31
35 29
36 29
37 30
38 34
39 38
40 14
41 40
42 26
43 33
44 1
45 44
46 25
47 14
48 2
49 30
50 26
51 46
52 34
53 32
54 31
55...

output:

result: