main function
s1 = [ ] NEW_LINE s2 = [ ] NEW_LINE s1 . append ( 34 ) NEW_LINE s1 . append ( 3 ) NEW_LINE s1 . append ( 31 ) NEW_LINE s2 . append ( 1 ) NEW_LINE s2 . append ( 12 ) NEW_LINE s2 . append ( 23 ) NEW_LINE