/** 
 * Multiplexor:
 * out = a if sel == 0
 *       b otherwise
 */

CHIP Mux {
    IN a, b, sel;
    OUT out;

    PARTS:
	Not(in=sel,out=notsel);
	And(a=a,b=notsel,out=out1);
	And(a=b,b=sel,out=out2);
	Or(a=out1,b=out2,out=out);
}