package main

import (
	"fmt"
	"math"
)

func main() {
	var N int
	var ans int
	fmt.Scan(&N)
	n1 := N/2
	for i:=0;i<n1;i++{
		ans += 1 * int(math.Pow(10, float64(i)))
	}
	if N%2==1{
		ans+=6*int(math.Pow(10, float64(n1-1)))
	}
	fmt.Println(ans)
}