import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

from math import isqrt

"""

n が平方数なら簡単

n が平方数でないとき

i * sqrt(n) < x となる i がいくつあるか

i * i  < x / n

"""
def func(x, n):
    return x - isqrt((x * x - 1) // n) - 1

n, m = na()

if n == 1:
    print("NaN")
    exit()

# for i in range(1, 10):
#     print(i, func(i, n))

ok = 10 ** 18
ng = 0
while ok - ng > 1:
    mid = ok + ng >> 1
    # print(mid, func(mid, n)
    if func(mid, n) >= m:
        ok = mid
    else:
        ng = mid

print(ok - 1)

# n, m = na()
# if n == 1:
#     print("NaN")