Introduction

My car speedometer was hacked! Instead of showing me how fast i'm driving, it just shows: "Vroooom!" Please help me know how fast i'm going.

Challenge

Take a string as input, and check if it matches the regex /^[Vv]ro*m!$/m. In English that means any line of the string must start with a capital or lowercase v, then a lowercase r, then any amount (including zero) of the lowercase letter o, then the exact string m!. There may be other lines, but the Vroom string must be on it's own line.

If you find a match, then you must count the amount of o's in the Vroom string and output it. If you don't find a match however, you should output any default value that can't be outputted otherwise (like -1 or an empty string)

Reminders

• I/O is in any reasonable format
  


• 
  Standard loopholes are banned


• Submission may be a full program or function


• Input is guaranteed to only have 1 Vroom string

Scoring

This is code-golf, so the shortest code in bytes wins. However, I will not mark any answer as accepted.

Test cases

Input

Vrom!

Output 1

Input

vrooooooom!

Output 7

Input

Hello, Vroom!

Output (none)

Input

Foo bar boo baz
Vrooom!
hi

Output 3

Input

Vrm!ooo

Output (none)

Input

PPCG puzzlers pie

Output (none)

Input

hallo
vROOOm!

Output (none)

PowerShell, 83 bytes

($args-split"`n"|%if(($x=[regex]::Match($_,"^[Vv]ro*m!$")).success)$x).length-4

Try it online!

-splits the input $args on `newlines, pipes those into a for loop. Each iteration, we check whether our [regex]::Match is a .success or not. If so, we leave $x (the regex results object) on the pipeline. Outside the loop, we take the .length property -- if it's the regex results object, this is the length of the match (e.g., "Vroom!" would be 6); if it's not a regex results object, the length is zero. We then subtract 4 to remove the counts for the Vrm! and leave that on the pipeline. Output is implicit. Outputs a -4 if no match is found.

SNOBOL4 (CSNOBOL4), 99 bytes

I	I =INPUT	:F(END)
	I POS(0) ('V' | 'v') 'r' ARBNO('o') . X 'm!' RPOS(0)	:F(I)
	OUTPUT =SIZE(X)
END

Try it online!

Pretty direct SNOBOL translation of the spec, reads each line until it finds one that matches ^[Vv]ro*m!$, then outputs the length of the o* bit.

Outputs nothing if no Vroom! can bound found.

Stax, 16 bytes

ü%.÷¶▌é⌂ü╥╪╛╪àG⌐

Run and debug it

sed 4.2.2, 20 bytes

-nr options required at the command-line.

s/^[Vv]r(o*)m!$/1/p

This outputs the speed in unary as the number of os.

Try it online!

JavaScript (Node.js), 41 bytes

a=>(l=/[Vv]r(o*)m!/.exec(a))&&l[1].length

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Powershell, 62 bytes

if("$args"-cmatch'(?ms).*^[Vv]r(o*)m!$.*')$Matches[1].Length

Explanation:

• 
  -cmatch means case-sensitive match;


• 
  (?ms) inside regexp means:
  
  
  • Use multiline mode. ^ and $ match the beginning and end of a line, instead of the beginning and end of a string.
  
  
  • Use single-line mode, where the period . matches every character (instead of every character except n)
  
  


• 
  $Matches[1] gives a group of o-sequence.

Test script:

$f = 

if("$args"-cmatch'(?ms).*^[Vv]r(o*)m!$.*')$Matches[1].Length



@(
,('Vrom!',1)
,('vrooooooom!',7)
,('Hello, Vroom!',$null)
,('Foo bar boo baz
Vrooom!
hi',3)
,('Vrm!ooo',$null)
,('PPCG puzzlers pie',$null)
,('hallo
vROOOm!',$null)
,('
Vrooom!
Vrooooom!
',5) # undefined behavior. By default regexp is greedy, therefore last Vroom displayed.
,('vrm!',0) # :)
) | % 
 $n,$expected = $_
 $result = &$f $n
 "$($result-eq$expected): $result"

Output:

True: 1
True: 7
True:
True: 3
True:
True:
True:
True: 5
True: 0