Например:
X:4 1 6 2 9 8
Y:1 3 4 6
INPUT "vvedite kol-vo elementov ",n
DIM x(n),y(n)
RANDOMIZE TIMER
PRINT "massiv x"
FOR i=1 TO n
x(i)=INT(RND*20)
PRINT x(i);" ";
NEXT
PRINT
FOR i=1 TO n
IF x(i) MOD 2=0 THEN k=k+1:y(k)=i
NEXT
PRINT "massiv y"
FOR i=1 TO k
PRINT y(i);" ";
NEXT