Wikipedia
The McNuggets version of the coin problem was introduced by Henri Picciotto,
who included it in his algebra textbook co-authored with Anita Wah. Picciotto
thought of the application in the 1980s while dining with his son at
McDonald's, working the problem out on a napkin. A McNugget number is
the total number of McDonald's Chicken McNuggets in any number of boxes.
In the United Kingdom, the original boxes (prior to the introduction of
the Happy Meal-sized nugget boxes) were of 6, 9, and 20 nuggets.

Task

Calculate (from 0 up to a limit of 100) the largest non-McNuggets
number (a number n which cannot be expressed with 6x + 9y + 20z = n
where x, y and z are natural numbers).




PROC Main()
  BYTE x,y,z,n
  BYTE ARRAY nuggets(101)
 
  FOR n=0 TO 100
  DO
    nuggets(n)=0
  OD
 
  FOR x=0 TO 100 STEP 6
  DO
    FOR y=0 TO 100 STEP 9
    DO
      FOR z=0 TO 100 STEP 20
      DO
        n=x+y+z
        IF n<=100 THEN
          nuggets(n)=1
        FI
      OD
    OD
  OD
 
  n=100
  DO
    IF nuggets(n)=0 THEN
      PrintF("The largest non McNugget number is %B%E",n)
      EXIT
    ELSEIF n=0 THEN
      PrintE("There is no result")
      EXIT
    ELSE
      n==-1
    FI
  OD
RETURN