import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")

n,s = map(int, input().split())
g = [1]
v = 1
for i in range(1,n+2):
    v *= i
    g.append(v)
def ps(n,v):
    """長さnの順列で、辞書順v番目
    """
    seen = [False]*n
    ans = []
    for i in range(n):
        num = v//g[n-i-1]
        count = 0
        for j in range(n):
            if seen[j]:
                continue
            if count==num:
                break
            if not seen[j]:
                count += 1
        ans.append(j)
        seen[j] = True
        v = v%g[n-i-1]
    return ans
def index(ps):
    """順列psの辞書順
    """
    n = len(ps)
    v = 0
    seen = [False] * n
    for i in range(n):
        num = 0
        for j in range(ps[i]):
            if not seen[j]:
                num += 1
        v += num * g[n-i-1]
        seen[ps[i]] = True
    return v
p = ps(s,n)
pp = [None]*s
for i,v in enumerate(p):
    pp[v] = i
print(index(pp))