module LUT4(input A, B, C, D, output Z);
    parameter [15:0] INIT = 16'h0000;
    wire [7:0] s3 = D ?     INIT[15:8] :     INIT[7:0];
    wire [3:0] s2 = C ?       s3[ 7:4] :       s3[3:0];
    wire [1:0] s1 = B ?       s2[ 3:2] :       s2[1:0];
    assign Z =      A ?          s1[1] :         s1[0];
    specify
        (A => Z) = 141;
        (B => Z) = 275;
        (C => Z) = 379;
        (D => Z) = 379;
    endspecify
endmodule