Answers for "1 billion users leetcode"

1 billion users leetcode

def sumDay(arr, t):
  running = 0
  for g in arr:
    running += (g ** t)
  return running

def search(arr, low, high):
  while low < high:
    mid = low + (high - low) // 2
    if sumDay(arr, mid) < 1000000000:
      low = mid + 1
    else:
      high = mid
  return high

def getBillionUsersDay(growthRates):
  i = 1
  users = sumDay(growthRates, i)
  if users >= 1000000000:
    return 1

# find the upper boundry
while users < 1000000000:
  i *= 2
  users = sumDay(growthRates, i)

# find the exact boundry
return search(growthRates, i // 2, i)