AOI_4_unit

module AOI_4_unit(y_out,x_in1,x_in2,x_in3,x_in4);
input x_in1,x_in2,x_in3,x_in4;
output y_out;
wire y1,y2;
and #1(y1,x_in1,x_in2);
and #1(y2,x_in3,x_in4);
nor #1(y_out,y1,y2);