package main

import . "fmt"

func main() {
	var n string
	Scan(&n)
	var a,b,c int
	Sscan(n[0:1], &a)
	Sscan(n[1:2], &b)
	Sscan(n[2:3], &c)
	if a+c==b {
		Println("Yes")
	} else {
		Println("No")
	}
	
}