position_list = [(0,0)]
def knight_move(inlist):
    y, x = inlist[0], inlist[1]
    outlist = [ (y+1, x+2), (y+2, x+1), (y-1, x+2), (y-2, x+1), (y+1, x-2), (y+2, x-1), (y-1, x-2), (y-2, x-1) ] 
    return outlist


for i in range(3):
    moved_list = []
    for j in position_list:
        moved_list += knight_move(j)

    
    position_list += moved_list
    position_list = list(set(position_list))


target = tuple( int(v) for v in input().split() )



if target in position_list:
    print("YES")
else:
    print("NO")