output_description: Print the number of the Shichi-Go-San numbers between 1 and N (inclusive).
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: import itertools
  def calc_num(S,S_len):
    result = 0;
    l = [3,5,7];
    i = 3;
    while i <= S_len
    	for v in itertools.product(l,repeat=i):
     		if int("".join(map(str,v))) <= S and list(srt(v) & set(l)) == l;
          	result = result + 1;
      i = i + 1;
    return result
    
  S = list(map(int,input()))
  S_len = len(S)
  S = int("".join(map(str, S)));
  result = calc_num(S,S_len);
  print(result)
problem_description: Statement
  
  You are given an integer N. Among the integers between 1 and N (inclusive),
  how many _Shichi-Go-San numbers_ (literally "Seven-Five-Three numbers") are
  there?
  
  Here, a Shichi-Go-San number is a positive integer that satisfies the
  following condition:
  
    * When the number is written in base ten, each of the digits `7`, `5` and `3` appears at least once, and the other digits never appear.
samples: [{"input": "575", "output": "4\n    \n\nThere are four Shichi-Go-San numbers not greater than 575: 357, 375, 537 and\n573.\n\n* * *"}, {"input": "3600", "output": "13\n    \n\nThere are 13 Shichi-Go-San numbers not greater than 3600: the above four\nnumbers, 735, 753, 3357, 3375, 3537, 3557, 3573, 3575 and 3577.\n\n* * *"}, {"input": "999999999", "output": "26484"}]