output_description: Output an integer representing the maximum number of products Mr. Takahashi
  can sell.
  
  * * *
input_description: Inputs are provided from Standard Inputs in the following form.
  
      
      
      N
      A_1
      :
      A_N
attempt: N=int(input())
  a=[0]*N
  for i in range(N):
      a.[i]=int(input())
  minimum=1
  count=0
  for i in  a:
     if(minimum<i):
         if i%minimum:
             count+= i//minimum
         else :
             count+= (i//minimum-1)
     else:
         minimum=max(minimum,i+1)
  print(count)
  
problem_description: Statement
  
  N people are waiting in a single line in front of the Takahashi Store. The
  cash on hand of the i-th person from the front of the line is a positive
  integer A_i.
  
  Mr. Takahashi, the shop owner, has decided on the following scheme: He picks a
  product, sets a positive integer P indicating its price, and shows this
  product to customers in order, starting from the front of the line. This step
  is repeated as described below.
  
  At each step, when a product is shown to a customer, if price P is equal to or
  less than the cash held by that customer at the time, the customer buys the
  product and Mr. Takahashi ends the current step. That is, the cash held by the
  first customer in line with cash equal to or greater than P decreases by P,
  and the next step begins.
  
  Mr. Takahashi can set the value of positive integer P independently at each
  step.
  
  He would like to sell as many products as possible. However, if a customer
  were to end up with 0 cash on hand after a purchase, that person would not
  have the fare to go home. Customers not being able to go home would be a
  problem for Mr. Takahashi, so he does not want anyone to end up with 0 cash.
  
  Help out Mr. Takahashi by writing a program that determines the maximum number
  of products he can sell, when the initial cash in possession of each customer
  is given.
samples: [{"input": "3\n    3\n    2\n    5", "output": "3\n    \n\nAs values of P, select in order 1, 4, 1.\n\n* * *"}, {"input": "15\n    3\n    1\n    4\n    1\n    5\n    9\n    2\n    6\n    5\n    3\n    5\n    8\n    9\n    7\n    9", "output": "18"}]