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).




 
# syntax: GAWK -f MCNUGGETS_PROBLEM.AWK
# converted from Go
BEGIN {
    limit = 100
    for (a=0; a<=limit; a+=6) {
      for (b=a; b<=limit; b+=9) {
        for (c=b; c<=limit; c+=20) {
          arr[c] = 1
        }
      }
    }
    for (i=limit; i>=0; i--) {
      if (!arr[i]+0) {
        printf("%d\n",i)
        break
      }
    }
    exit(0)
}
 