import sys

sys.setrecursionlimit(10**6)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.buffer.readline())
def MI(): return map(int, sys.stdin.buffer.readline().split())
def MI1(): return map(int1, sys.stdin.buffer.readline().split())
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def LI1(): return list(map(int1, sys.stdin.buffer.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def BI(): return sys.stdin.buffer.readline().rstrip()
def SI(): return sys.stdin.buffer.readline().rstrip().decode()
dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
inf = 10**16
# md = 998244353
md = 10**9+7

fac=[1]
for i in range(1,21):fac.append(fac[-1]*i)
n,s=MI()
can=list(range(s))
per=[0]*s
for i in range(s):
    j=n//fac[s-1-i]
    n-=fac[s-1-i]*j
    per[i]=can[j]
    del can[j]
# print(per)

pi=[(p,i) for i,p in enumerate(per)]
pi.sort()
aa=[i for p,i in pi]
# print(aa)

can=list(range(s))
ans=0
for i,a in enumerate(aa):
    j=can.index(a)
    del can[j]
    ans+=fac[s-1-i]*j
print(ans)