```
#!/usr/local/bin/python3
import sys
def print_factorial( user_val ):
if( user_val < 1 ):
return( 1 )
else:
return( print_factorial( user_val - 1 ) * user_val )
if( __name__ == "__main__" ):
if( len( sys.argv ) == 2 ):
print( print_factorial( int ( sys.argv[ 1 ] ) ) )
else:
sys.stderr.write( "usage: %s <integer>\n" % sys.argv[ 0 ] )
exit( 0 )
```
Answer:
When searching for articles using library databases, the following tips should increase the relevance of your results. Quotation marks around two or more keywords - phrase searching - ensures that the results will include the exact phrase.
Explanation:
I think it would be a hard drive
True.
Windows is an operating system built by Microsoft. Chrome and Android are operating systems built by Google. MacOS (Macbook pro etc) and iOS (iPhone, iPad, Apple Watch etc) are operating systems built by Apple.
Engineers build applications or apps for all of the above operating systems (OS). For example, Microsoft Word menus will look slightly different on Windows vs on a Mac. The underlying functionality maybe the same but the way it looks may have subtle differences.
Think of the OS as the foundation of a building. Once you have the foundation, you can build a house, a skyscraper, an office building etc depending on what you want to build.
