Extract a string from a given string You are given a string and two characters. You have to print the string between these characters from the string.

Input

Input will first contain a string (not empty or null). In the next line, there will be two characters separated by a space.

Challenge

Return the string between the two characters

Example

Hello! What's your name?
! ?


should result in the output:

" What's your name"


Rules


The string will not be longer than 100 characters and will only contain ASCII characters in range (space) to ~(tilde) (character codes 0x20 to 0x7E, inclusive). See ASCII table for reference.
You must take input from the stdin( or closest alternative ).
The output should be surrounded with quotes(").
You can write a full program, or a function which takes input, and outputs the final string
The two characters will only contain ASCII characters in range (space) to ~(tilde) (character codes 0x20 to 0x7E, inclusive). See ASCII table for reference.
There is no guarantee that both the characters will be in the string.
If any of the characters is not found in the string, print "null".
If any of the characters is found more than one times (unless both the characters are same) in a string, print "null".
If both the characters are the same character, print the string "null".


Test Cases

1)

&lt;HTML&gt;code&lt;/HTML&gt;
&gt; &lt;                       --&gt; "null"


2)

What's what?
' '                       --&gt; "null"


3)

abcdefghijklmnopqrstuvwxyz
n k                       --&gt; "lm"


4)

Testing...
e T                       --&gt; ""


5)

Last test-case
  -                       --&gt; "test"


Scoring

This is code golf, so the shortest submission (in bytes) wins.
CJam, 34 33 32 bytes

'"l_l2%&amp;2*2&gt;NerN/0"null"t_,3=='"


Try it online in the CJam interpreter.

Idea


Remove the second character from line 2.
Form a string consisting of a single copy of all characters that both lines have in common.
Repeat the resulting string twice and discard its first two characters.

This results in a two-character string (if the characters from line 2 are different and both occur in line 1) or an empty string.
Replace the characters of the resulting string in line 1 by linefeeds.
Split line 1 at linefeeds.

The resulting array's second element will be the desired string if the array contains exactly three chunks.
Replace the first element of the array with the string null.
Retrieve the second element of the array if its length is 3 and the first otherwise.
Prepend and append a double quote.


Code

'"       e# Push a double quote.
l_       e# Read one line from STDIN. Push a copy.
l2%      e# Read one line from STDIN. Only keep characters at odd indexes.
&amp;        e# Intersect both strings.
2*2&gt;     e# Repeat the intersection twice and discard the first two characters.
Ner      e# Replace the characters of the resulting string with linefeeds.
N/       e# Split the result at linefeeds.
0"null"t e# Replace the first element of the resulting array with "null".
_,3=     e# Push 1 if the length of the array is 3 and 0 otherwise.
=        e# Retrieve the corresponding element from the array.
'"       e# Push a double quote.