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 nota, notb, w1, w2;
    // TODO: instantiate required gates
    not_gate n1(.a(a), .y(nota));
    not_gate n2(.a(b), .y(notb));
    and_gate a1(.a(a), .b(notb), .y(w1));
    and_gate a2(.a(nota), .b(b), .y(w2));
    or_gate o1(.a(w1), .b(w2), .y(y));

endmodule