n,k=map(int,input().split())
if n%2==1:
    if k<=n//2+1:
        print('YES')
    else:
        print('NO')
else:
    if k<=n//2:
        print('YES')
    else:
        print('NO') n,k=map(int,input().split()) n map(int,input().split()) map int input().split() ().split () input split k if n%2==1:
    if k<=n//2+1:
        print('YES')
    else:
        print('NO')
else:
    if k<=n//2:
        print('YES')
    else:
        print('NO') n%2==1 n%2 n 2 1 if k<=n//2+1:
        print('YES')
    else:
        print('NO') k<=n//2+1 k n//2+1 n//2 n 2 1 print('YES') print 'YES' print('NO') print 'NO' if k<=n//2:
        print('YES')
    else:
        print('NO') k<=n//2 k n//2 n 2 print('YES') print 'YES' print('NO') print 'NO' n,k=map(int,input().split()) map(int,input().split()) n k=map(int,input().split()) map(int,input().split()) k
n,k=map(int,input().split())
if n%2==1:
    if k<=n//2+1:
        print('YES')
    else:
        print('NO')
else:
    if k<=n//2:
        print('YES')
    else:
        print('NO')
