input:

10
1 2
1 3
1 4
1 5
2 3
2 4
2 5
3 4
3 5
4 5

output:

1 3
2 3
2 4
2 5
2 3
2 4
2 5
1 4
1 5
1 5

result:

wrong answer 1st numbers differ - expected: '3', found: '1'