64. Full Adder

How do you plan to solve it?

// Half Adder primitive
module half_adder (
    input  a, b,
    output sum, carry
);
    assign sum = a ^ b;
    assign carry = a & b;    
endmodule

// Full Adder using 2 Half Adders
module full_adder_struct (
    input  a, b, cin,
    output sum, cout
);
    wire sum1, carry1, carry2;
    half_adder ha1(a, b, sum1, carry1);
    half_adder ha2(sum1, cin, sum, carry2);
    or g1(cout, carry1, carry2);
endmodule