Generate two arrays of length 10, whose elements are unique to each other.

CODE:

class mem;
  rand int a[10];
  rand int b[10];
  
  constraint c_a_b {
    unique { b };
    foreach ( a[i] ) {
      b[i] inside {[1:20]};
      a[i] inside {[1:20]};
      !(a[i] inside b);      
    }
  }
  
  function void post_randomize();
    $display ("A:%p",a);
    $display ("B:%p",b);
  endfunction: post_randomize
    
endclass: mem
    
module top;
  mem m;
  
  initial begin
    m = new;
    void'(m.randomize());
    
  end
endmodule: top

OUTPUT:

Compiler version U-2023.03-SP2_Full64; Runtime version U-2023.03-SP2_Full64; Aug 12 11:01 2025
A:'{4, 5, 17, 19, 8, 4, 5, 12, 9, 15}
B:'{18, 16, 3, 20, 1, 11, 7, 2, 10, 14}
V C S S i m u l a t i o n R e p o r t

Single Linked List in System Verilog

 Lets code a simple singly Linked List which traverse from head to tail in one direction.

Requirement is simple, you will have a Node which contains two main elements, data and pointer to next node.

On adding a new node, the new node should create a handle of the old node and assign the pointer to the new one.

CODE:

class Node;
  int id;
  int data;
  Node next_node;
  
  function new ( int i );
    id = i;
    next_node = null;
  endfunction: new
  
  function void load_data ( int val );
    data = val;
  endfunction: load_data

  function void add_node ( Node node );
    node.next_node  = new(id);
    node.next_node  = this;
  endfunction: add_node
  
 endclass: Node
  
  module top;
    Node n[10];
    
    initial begin
      foreach ( n[i] ) begin
        n[i]      = new(i);
        n[i].data = $urandom_range(10,100);
        if(i>0) n[i].add_node(n[i-1]);           
      end 
      
      foreach ( n[i] ) begin        
        if(i==9) 
          $display ( "NODE ID:%0d Data:%0d NEXT_PTR:NULL", n[i].id,n[i].data );
        else 
          $display ( "NODE ID:%0d Data:%0d NEXT_PTR:%0d", n[i].id,n[i].data,n[i].next_node.id );
      end
    end        
  endmodule: top

RESULT:

Compiler version U-2023.03-SP2_Full64; Runtime version U-2023.03-SP2_Full64; Aug 12 10:17 2025
NODE ID:0 Data:54 NEXT_PTR:1
NODE ID:1 Data:62 NEXT_PTR:2
NODE ID:2 Data:68 NEXT_PTR:3
NODE ID:3 Data:44 NEXT_PTR:4
NODE ID:4 Data:75 NEXT_PTR:5
NODE ID:5 Data:88 NEXT_PTR:6
NODE ID:6 Data:89 NEXT_PTR:7
NODE ID:7 Data:72 NEXT_PTR:8
NODE ID:8 Data:62 NEXT_PTR:9
NODE ID:9 Data:53 NEXT_PTR:NULL
V C S S i m u l a t i o n R e p o r t