user
Using the in-built capabilities of your language, calculate the integer value of:

```
        
  
    
      
        
          
            
              5
              
                
                  4
                  
                    
                      3
                      
                        2
                      
                    
                  
                
              
            
          
        
      
    
    {\displaystyle {\displaystyle 5^{4^{3^{2}}}}}
  


```

* Confirm that the first and last twenty digits of the answer are:

```
     62060698786608744707...92256259918212890625

```

* Find and show the number of decimal digits in the answer.

Note:

* Do not submit an *implementation* of arbitrary precision arithmetic. The intention is to show the capabilities of the language as supplied. If a language has a single, overwhelming, library of varied modules that is endorsed by its home site – such as CPAN for Perl or Boost for C++ – then that *may* be used instead.
* Strictly speaking, this should not be solved by fixed-precision numeric libraries where the precision has to be manually set to a large value; although if this is the **only** recourse then it may be used with a note explaining that the precision must be set manually to a large enough value.

Related tasks

* Long multiplication
* Exponentiation order
* exponentiation operator
* Exponentiation with infix operators in (or operating on) the base
assistant
(formerly Perl 6)

**Works with**: Rakudo version 2022.07

```
given [**] 5, 4, 3, 2 {
  use Test;
  ok /^ 62060698786608744707 <digit>* 92256259918212890625 $/,
     '5**4**3**2 has expected first and last twenty digits';
  printf 'This number has %d digits', .chars;
}

```

Output:

```
ok 1 - 5**4**3**2 has expected first and last twenty digits
This number has 183231 digits
```