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
);
    wire w1,w2,w3,w4;
    // TODO: declare intermediate wires
    not_gate n1(.a(b),.y(w1));
    and_gate a1(.a(a),.b(w1),.y(w2));
    not_gate n2(.a(a),.y(w3));
    and_gate a2(.a(w3), .b(b),.y(w4));
    or_gate o(.a(w2),.b(w4),.y(y));
    // TODO: instantiate required gates

endmodule