// 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 w1,w2,w3;
half_adder a1(.a(a),.b(b),.sum(w1),.carry(w2));
half_adder a2(.a(w1),.b(cin),.sum(sum),.carry(w3));
or a3 (cout,w2,w3);
endmodule