How do you plan to solve it?
// ============================================================
// Basic Gates (given)
// ============================================================
module and_gate(input a, b, output y);
assign y = a & b;
endmodule
module or_gate(input a, b, output y);
assign y = a | b;
endmodule
module not_gate(input a, output y);
assign y = ~a;
endmodule
// ============================================================
// XOR Gate
// ============================================================
module xor_gate (
input a, b,
output y
);
// TODO: declare intermediate wires
wire x1, x2, bu_a, bu_b;
// TODO: instantiate required gates
not_gate buA(.a(a), .y(bu_a));
not_gate buB (.a(b), .y(bu_b));
and_gate tren(.a(a), .b(bu_b), .y(x1));
and_gate duoi(.a(bu_a), .b(b), .y(x2));
or_gate kq(.a(x1), .b(x2), .y(y));
endmodule