`timescale 1ns/1ns
module mux4_1(
input [1:0]d1,d2,d3,d0,
input [1:0]sel,
output[1:0]mux_out
);
//*************code***********//
wire[1:0] d1,d2,d3,d0;
wire[1:0]sel;
reg [1:0]mux_out;
always@(*) begin
case(sel)
2'b11: mux_out=d0;
2'b10: mux_out=d1;
2'b01: mux_out=d2;
2'b00: mux_out=d3;
endcase
end
//*************code***********//
endmodule