func countSetsRecursively(lastLen, lastK int, current vector.StringVector, usedDigits map[int]bool,
primes [][]map[int]bool, primesByLen [][]string) int64 {
currentLength := len(usedDigits)
if currentLength == 9 {
//fmt.Println(current)
return 1
} else if currentLength > 9 {
panic("w00t")
}
count := int64(0)
for length, v := range primes {
if currentLength+length > 9 {
break
}
if length < lastLen {
continue
}
for k, digits := range v {
if k <= lastK {
continue
}
joinedDigits := joinDigitMaps(usedDigits, digits)
if len(joinedDigits) == currentLength+len(digits) {
currentCopy := current.Copy()
currentCopy.Push(primesByLen[length][k])
count += countSetsRecursively(length, k, currentCopy, joinedDigits, primes, primesByLen)
}
}
lastK = -1
}
return count
}