func isReverseTruncatablePrime(num string) bool {
length := len(num)
for i := 0; i < length-1; i++ {
x, _ := strconv.Atoi(num[length-1-i:])
if !primes.IsPrime(x) {
fmt.Println(" X Not Reverse Truncatable Prime becuase", x, "is not prime")
return false
}
}
fmt.Print(" +Reverse Truncatable Prime")
return true
}
func main() {
result := 2
for i := []int{1, 2, 3}; len(i) < 10; i = append(i, i[len(i)-1]+1) {
fmt.Println(i)
pandigital := operations.Permutations(i)
for _, x := range pandigital {
if primes.IsPrime(x) && x > result {
fmt.Println(x)
result = x
}
}
}
}
func main() {
numbers := []string{"1", "3", "7", "9"}
results := make([]int, 0)
current := map[string]int{"2": 0, "3": 0, "5": 0, "7": 0}
for {
next := make(map[string]int)
for k, _ := range current {
for _, n := range numbers {
newNum, _ := strconv.Atoi(k + n)
fmt.Print("Checking ", newNum)
if primes.IsPrime(newNum) {
fmt.Print(" +Prime")
next[k+n] = 1
if isReverseTruncatablePrime(k + n) {
fmt.Println(" !!!FOUND:", newNum, "!!!")
results = append(results, newNum)
}
} else {
fmt.Println(" X Not Prime")
}
}
}
fmt.Println(next)
fmt.Println(results)
if len(next) == 0 {
break
} else {
current = next
}
}
fmt.Println(results)
sum := 0
for _, x := range results {
sum += x
}
fmt.Println(sum)
}