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);
    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
);
    wire a_bar, b_bar, a_and_b_bar, a_bar_and_b;

    and_gate AND0(.a(a), .b(b_bar), .y(a_and_b_bar));
    not_gate NOT0(.a(a), .y(a_bar));

    and_gate AND1(.a(a_bar), .b(b), .y(a_bar_and_b));
    not_gate NOT1(.a(b), .y(b_bar));

    or_gate OR0(.a(a_and_b_bar), .b(a_bar_and_b), .y(y));

endmodule