a={case[x],s->x
case[x,*y],s->x+s+a(y,s)}
g={n,x->a(split(x,n)," "+n+" ")}
stdin|{x->a(sort(split(g("0",g("1",g("2",g("3",g("4",g("5",g("6",g("7",g("8",x))))))))))),"")}|puts