For problem statement at 0-999/300-399/320-329/320/problemA.txt this is a correct solution, but verifier at 0-999/300-399/320-329/320/verifierA.go ends with ok 200 can you fix the verifier? package main

import (
	"fmt"
	"strings"
)

func main() {
	var s string
	if _, err := fmt.Scan(&s); err != nil {
		return
	}

	for i := 0; i < len(s); i++ {
		if s[i] != '1' && s[i] != '4' {
			fmt.Println("NO")
			return
		}
	}

	if s[0] == '4' || strings.Contains(s, "444") {
		fmt.Println("NO")
		return
	}

	fmt.Println("YES")
}