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 [3:0]w;
    // TODO: instantiate required gates
    not_gate n0(a,w[0]);
    not_gate n1(b,w[1]);
    and_gate a0(a,w[1],w[2]);
    and_gate a1(b,w[0],w[3]);
    or_gate o0(w[3],w[2],y);
endmodule