def in_str(needle, haystack)
  for i in (0..haystack.chars.length - 1)
    if needle.chars[0] == haystack.chars[i]
      found = true
      for j in (0..needle.chars.length - 1)
        if needle[j] != haystack[i + j]
          found = false
          break
        end
      end
      if found
        puts "Found needle #{needle} in #{haystack} at position #{i}"
      end
    end
  end
end