for i := N downto 1  
         for j :=  2 toi do 
              if a[j-1] > a[j]then 
                   swap(a[j-1], a[j]) 
    example: 
    3 6 2 3 1 2
    9 2 6 1 3 3
    2 7 1 5 5 5
    7 1 5 6 6 6
    1 5 7 7 7 7
    5 9 9 9 9 9