10 DEF FN e(a)=a-INT (a/2)*2-1
20 DEF FN h(a)=INT (a/2)
30 DEF FN d(a)=2*a
40 LET x=17: LET y=34: LET tot=0
50 IF x<1 THEN GO TO 100
60 PRINT x;TAB (4);
70 IF FN e(x)=0 THEN LET tot=tot+y: PRINT y: GO TO 90
80 PRINT "---"
90 LET x=FN h(x): LET y=FN d(y): GO TO 50
100 PRINT TAB (4);"===",TAB (4);tot