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
);
    wire sum1, carry1, carry2;
    // Write code here
    half_adder ha1 (.a(a),    .b(b),   .sum(sum1), .carry(carry1));
    half_adder ha2 (.a(sum1), .b(cin), .sum(sum), .carry(carry2));
    assign cout = carry1 | carry2;

endmodule