N,S=map(int,input().split())
P=list(range(S))
X=[]
for i in range(1,S+1):
  X.append(N%i)
  N//=i
X=X[::-1]
Q=[]
for i in range(S):
  Q.append(P[X[i]])
  del P[X[i]]
D=dict()
for i in range(S):
  D[Q[i]]=i
R=[D[i] for i in range(S)]
P=list(range(S))
A=0
F=1
for i in range(S):
  F*=i+1
for i in range(S):
  F//=S-i
  A+=P.index(R[i])*F
  del P[P.index(R[i])]
print(A)