import java.util.*;
public class Main{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int answer = (a + b + c) / 3;
		if(answer == a+b+c){
			System.out.println("Yes");
		}else{
			System.out.println("No");
		}
	}

}
