NR name output1
1  a    before
1  b    before
1  i    before
1  x    before
1  y    before
2  a    before
2  b    before
2  i    before
2  x    before
2  y    before
3  a    before
3  b    before
3  i    before
3  x    before
3  y    before
4  a    before
4  b    before
4  i    before
4  x    before
4  y    before
5  a    before
5  b    before
5  i    before
5  x    before
5  y    before
6  a    before
6  b    before
6  i    before
6  x    before
6  y    before
7  a    before
7  b    before
7  i    before
7  x    before
7  y    before
8  a    before
8  b    before
8  i    before
8  x    before
8  y    before
9  a    before
9  b    before
9  i    before
9  x    before
9  y    before
10 a    before
10 b    before
10 i    before
10 x    before
10 y    before
