9. XOR Gate Using Basic Gates

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);
    // write code here for or gate
    assign y = a | b;
endmodule

module not_gate(input a, output y);
    // write code here for not gate
    assign y = !a;
endmodule

// ============================================================
// XOR Gate
// ============================================================
module xor_gate (
    input  a, b,
    output y
);
    // TODO: declare intermediate wires
    wire a_not_b;
    wire not_a_b;
    wire not_b;
    wire not_a;

    // TODO: instantiate required gates

    not_gate b_not (.a(b), .y(not_b));
    not_gate a_not (.a(a), .y(not_a));

    and_gate a_not_b_gate(.a(a), .b(not_b), .y(a_not_b));
    and_gate not_a_b_gate(.a(not_a), .b(b), .y(not_a_b));

    or_gate or_g(.a(a_not_b), .b(not_a_b), .y(y));

endmodule