def add(a = 0,b = 0):
    s = str(a) + "," + str(b)
    if s not in li:
        li2.append(s)

ss = input().split()

z = ss[0] + "," + ss[1]

li = ["0,0"]
li2 = []
f = 0

for i in range(3):
    for j in range(f,len(li)):
        ss = li[j].split(',')
        x = int(ss[0])
        y = int(ss[1])

        a = x - 2
        b = y - 1
        add(a,b)
        a = x - 2
        b = y + 1
        add(a,b)
        a = x - 1
        b = y - 2
        add(a,b)
        a = x - 1
        b = y + 2
        add(a,b)
        a = x + 1
        b = y - 2
        add(a,b)
        a = x + 1
        b = y + 2
        add(a,b)
        a = x + 2
        b = y - 1
        add(a,b)
        a = x + 2
        b = y + 1
        add(a,b)
        
    f = len(li)
    li += li2
    li2.clear()
        
if z in li:
    print("YES")
else:
    print("NO")