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).




fn mcnugget(limit int) {
    mut sv := []bool{len: limit+1} // all false by default
    for s := 0; s <= limit; s += 6 {
        for n := s; n <= limit; n += 9 {
            for t := n; t <= limit; t += 20 {
                sv[t] = true
            }
        }
    }
    for i := limit; i >= 0; i-- {
        if !sv[i] {
            println("Maximum non-McNuggets number is $i")
            return
        }
    }
}
 
fn main() {
   mcnugget(100)
}