i am willing to this project simple project
module adder_4(a,b,cin,s,cout);
input[3:0] a,b;
input cin;
output[3:0] s;
output cout;
wire c1, c2, c3;
FullAdder fa0(a[0], b[0], cin, c1, s[0]);
FullAdder fa1(a[1], b[1], cin, c1, s[1]);
FullAdder fa2(a[2], b[2], cin, c1, s[2]);
FullAdder fa3(a[3], b[3], cin, c1, s[3]);
endmodule