64. Full Adder

How do you plan to solve it?

// Half Adder primitive
module half_adder (
    input  a, b,
    output sum, carry
);
    // Write code here
    xor (sum, a, b);
    and (carry, a, b);
endmodule

// Full Adder using 2 Half Adders
module full_adder_struct (
    input  a, b, cin,
    output sum, cout
);
    // Write code here
wire w1, c1, c2;
half_adder hd1(.a(a), .b(b), .sum(w1), .carry(c1));
half_adder hd2(.a(w1), .b(cin), .sum(sum), .carry(c2));
or (cout, c1, c2);

endmodule