fork download
  1. [0,1,4,5,6,8,9].combination(2){|x| puts x.join(" ") }
Success #stdin #stdout 0.01s 6292KB
stdin
Standard input is empty
stdout
0 1
0 4
0 5
0 6
0 8
0 9
1 4
1 5
1 6
1 8
1 9
4 5
4 6
4 8
4 9
5 6
5 8
5 9
6 8
6 9
8 9