r, b = map(int, input().split())
t = r + b


l_ = 0
r_ = t + 1
while r_ - l_ > 1:
    m = (l_ + r_) // 2
    if m * (m + 1) * (2 * m + 1) // 6 <= t:
        l_ = m
    else:
        r_ = m

print(l_ - 1)