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ECJTU_ACM 11级队员2012年暑假训练赛（8）

4:30:00

 

 

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G - Nearly Lucky Number

Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u

     

Description

Petya loves lucky numbers. We all know that lucky numbers are the positive integers whose decimal representations contain only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.

Unfortunately, not all numbers are lucky. Petya calls a number nearly lucky if the number of lucky digits in it is a lucky number. He wonders whether number n is a nearly lucky number.

Input

The only line contains an integer n (1 ≤ n ≤ 10¹⁸).

Please do not use the %lld specificator to read or write 64-bit numbers in С++. It is preferred to use the cin, cout streams or the %I64d specificator.

Output

Print on the single line "YES" if n is a nearly lucky number. Otherwise, print "NO" (without the quotes).

Sample Input

Input

40047

Output

NO

Input

7747774

Output

YES

Input

1000000000000000000

Output

NO

Hint

In the first sample there are 3 lucky digits (first one and last two), so the answer is "NO".

In the second sample there are 7 lucky digits, 7 is lucky number, so the answer is "YES".

In the third sample there are no lucky digits, so the answer is "NO".

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Server Time: 

2012-08-13 10:52:34

 

 

 

1 // Project name : G 2 // File name    : main.cpp 3 // Author       : iCoding 4 // E-mail       : honi.linux@gmail.com 5 // Date & Time  : Fri Aug 10 15:24:28 2012 6  7  8 #include 
     
       9 #include 
      
       10 #include 
       
        11 #include 
        
         12 #include 
         
          13 using namespace std;14 15 /*************************************************************************************/16 /* data */17 18 19 /*************************************************************************************/20 /* procedure */21 22 23 /*************************************************************************************/24 /* main */25 int main()26 {27     string s;28     while (cin >> s)29     {30         int count = 0;31         int top = s.length() - 1;32         for (int i = 0; i <= top; i++)33         {34             if (s[i] == '4' || s[i] == '7')35             {36                 count++;37             }38         }39 40         //cout << count << endl;41 42         bool yes = true;43         if (count == 0)44         {45             yes = false;46         }47         while (yes == true && count)48         {49             if (count % 10 == 4 || count % 10 == 7)50             {51                 count /= 10;52             }53             else54             {55                 yes = false;56             }57         }58 59         if (yes)60         {61             cout << "YES" << endl;62         }63         else64         {65             cout << "NO"  << endl;66         }67     }68     return 0;69 }70 71 // end 72 // Code by Sublime text 273 // iCoding@CodeLab