Дан массив из N чисел. N — четное

Program Pr1; uses crt; var mas: array[1… 12] of integer; i,b: integer; Beginclrscr; randomize; for i: =1 to 12 do begin mas[i]: =random (10); write (mas[i]); end; for i: =1 to 12 do if i mod 2<>0 then begin b: =mas[i]; mas[i]: =mas[i+1]; mas[i+1]: =b; end; writeln; for i: =1 to 12 do write (mas[i]); end.