import decimal

decimal.getcontext().prec = 1000
N, M = map(decimal.Decimal, input().split())

if N == 1:
    print("NaN")
    exit(0)

ok, ng = 0, 10**20
while ok + 1 < ng:
    m = decimal.Decimal((ok + ng) // 2)
    x = (m - m/(N.sqrt())).__floor__()
    # print(m,x)
    if x >= M:
        ng = m
    else:
        ok = m
print(ok)