//2024-1-10 姜青羊
//case语句实现多路选择逻辑

`timescale 1ns/10ps
module fn_sw (
                        a,
                        b,
                        sel,
                        y
                    );

input                   a,b;
input[1:0]              sel;
output                  y;

reg                     y;

always @(a or b or sel)
begin
    case(sel)
    2'b00: begin  y<=a&b;   end
    2'b01: begin  y<=a|b;   end
    2'b10: begin  y<=a^b;   end
    2'b11: begin  y<=~(a^b) end
    endcase
end

endmodule

//--------testbench---------

module tb_fn_sw ();
    
endmodule