A,B = list(map(int, input().split()))
from collections import deque
que = deque()
que.append([A,B])
comb=set()
comb.add((A,B))
while que:
    a,b = que.popleft()
    if a==0 or b==0:
        print("Yes")
        exit()
    if a%2==b%2==0:
        if (a%2,b-1) not in comb:
            comb.add((a%2,b-1))
            que.append([a%2,b-1])
        if (a-1,b%2) not in comb:
            comb.add((a-1,b%2))
            que.append([a-1,b%2])
    elif a%2==0:
        if (a%2,b-1) not in comb:
            comb.add((a%2,b-1))
            que.append([a%2,b-1])
    elif b%2==0:
        if (a-1,b%2) not in comb:
            comb.add((a-1,b%2))
            que.append([a-1,b%2])

print("No")