Tackling a constraint in post_randomize()

[nitin62goel]

you can use below constraints

rand bit [31:0] array;
bit [32:0] array_n;

function pre_randomize();
   array_n = array <<1;
endfunction

constraint cnt_c {
                               $countones(array) == 22;
                               $countones(array^array_n) == 2;
                              }