module FSM_user_coding(
    input w,clk,aclr,
    output reg z);

    reg [3:0]    y_Q, Y_D;

    localparam [3:0]
            A = 4'b0000,
            B = 4'b0001,
            C = 4'b0010,
            D = 4'b0011,
            E = 4'b0100,
            F = 4'b0101,
            G = 4'b0110,
            H = 4'b0111,
            I = 4'b1000;
    always @(*)
    case (y_Q)
        A:  if (!w) Y_D = B;    else Y_D = F;
        B:  if (!w) Y_D = C;    else Y_D = F;
        C:  if (!w) Y_D = D;    else Y_D = F;
        D:  if (!w) Y_D = E;    else Y_D = F;
        E:  if (!w) Y_D = E;    else Y_D = F;
        F:  if (!w) Y_D = B;    else Y_D = G;
        G:  if (!w) Y_D = B;    else Y_D = H;
        H:  if (!w) Y_D = B;    else Y_D = I;
        I:  if (!w) Y_D = B;    else Y_D = I;
        default:    Y_D = 4'bxxxx;
    endcase
    always @(posedge clk,negedge aclr)
        if (~aclr)      y_Q <= 0;
        else        y_Q <= Y_D;

    always @(*)
        z = (y_Q == E) | (y_Q == I);
endmodule