64. Full Adder

How do you plan to solve it?

// Half Adder primitive
module half_adder (
    input  a, b,
    output sum, carry
);
   xor w1(sum,a,b);
   and w2(carry,a,b); // Write code here

endmodule

// Full Adder using 2 Half Adders
module full_adder_struct (
    input  a, b, cin,
    output sum, cout
);
    // Write code here
wire sum1,carry1,carry2;
half_adder w1(.sum(sum1),.carry(carry1),.a(a),.b(b));
half_adder w2(.sum(sum),.carry(carry2),.a(sum1),.b(cin));
or w3(cout,carry2,carry1);

endmodule