In reply to stupidkris1010:
I am using this one which works fine, but looking for comments to optimize it further/ find other efficient way:
task randomize_list;
bit list[];
list = new[32];
$display("Random list:\n");
randomize(list) with {
list.sum < 32;
foreach(list[i]) if(i>0 && list[i]) list[i-1] != 1'b0;
};
for(int i=0;i<32;i++)
$display("%1b", list[i]);
endtask