needle in the haystack.go

package main

import "fmt"

func main() {
	fmt.Printf("%v\n", find("apple", "ale")) // true
	fmt.Printf("%v\n", find("apple", "alp")) // false
}

func find(haystack, needle string) bool {
	if len(needle) == 0 {
		return true
	}
	for i, c := range haystack {
		if c == int32(needle[0]) {
			return find(haystack[i:], needle[1:])
		}
	}
	return false
}