N, K = map(int, input().split())

if N < K:
    print(1)
elif N == K or K == 1:
    print(0)
else:
    print(N - K) N, K = map(int, input().split()) N map(int, input().split()) map int input().split() ().split () input split K if N < K:
    print(1)
elif N == K or K == 1:
    print(0)
else:
    print(N - K) N < K N K print(1) print 1 elif N == K or K == 1:
    print(0) N == K or K == 1 N == K N K K == 1 K 1 print(0) print 0 print(N - K) print N - K N K 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 < K:
    print(1)
elif N == K or K == 1:
    print(0)
else:
    print(N - K)