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: #include <iostream>
  #include <iomanip>
  #include <vector>
  #include <stack>
  #include <queue>
  #include <set>
  #include <map>
  #include <algorithm>
  #include <cstdio>
  #include <utility>
  #include <string>
  #include <cmath>
  #include <cstdlib>
  #include <cstring>
  #include <deque>
  #include <numeric>
  
  using namespace std;
  
  typedef uint64_t u64;
  typedef int64_t s64;
  typedef uint32_t u32;
  typedef int32_t s32;
  typedef vector<s32> vs32;
  typedef vector<u32> vu32;
  typedef vector<s64> vs64;
  typedef vector<u64> vu64;
  
  const double PI=3.14159265358979323846;
  
  #define MAX(x, y) ((x) < (y) ? (y) : (x))
  #define MIN(x, y) ((x) > (y) ? (y) : (x))
  
  #define rep(i, N) for(int i = 0; i < N; ++i)
  
  #define CEIL(x, y) (((x) + (y) - 1) / (y))
  #define MOD 1000000007ULL
  
  #define IN(l, r, x) ((l) <= (x) && (x) < (r))
  
  int N;
  s64 cand[] = {7, 5, 3};
  
  bool ok(s64 x)
  {
      bool t = false, f = false, s = false;
      while (x)
      {
          if (x % 10 == 3) t = true;
          else if (x % 10 == 5) f = true;
          else if (x % 10 == 7) s = true;
          x /= 10;
      }
      return t & f & s;
  }
  
  s64 dfs(s64 x)
  {
      if (x > N) return 0;
  
      int ret = 0;
      if (ok(x)) ret = 1;
  
      rep (i, 3)
      {
          ret += dfs(x * 10 + cand[i]);
      }
      return ret;
  }
  
  int main()
  {
      cin.tie(0);
      ios::sync_with_stdio(false);
  
      cin >> N;
      int ans = 0;
      rep (i, 3)
      {
          ans += dfs(cand[i]);
      }
      cout << ans << "\n";
      return 0;
  }
  
  
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"}]