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
    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
);
    // Write code here
    wire s1,c1;
    wire c2;
    half_adder a1(.a(a),.b(b),.sum(s1),.carry(c1));
    half_adder a2(.a(s1),.b(cin),.sum(sum),.carry(c2));
    assign cout = c1 | c2;

endmodule