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 s,c0,c1;
half_adder Ha1(a,b,s,c0);
half_adder Ha2(s,cin,sum,c1);
assign cout=c0|c1;

endmodule