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problem with removing spaces in the string

P: n/a
Hi,

Suppose I have a string like this:

"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"

In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?

regards

Sep 19 '07 #1
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11 Replies


P: n/a
ramu wrote:
Suppose I have a string like this:

"I have a string \"and a inner string\\\" I want to remove
space in this string but not in the inner string"

In the above string I have to remove spaces, but not in the
inner string(\"and a inner string\\\"). Will anyone please
tell me how to do this?
No problem. I suppose you have an input like

char s[] = "I have a string \"and a inner string\\\" I want"
" to remove space in this string but not in the "
"inner string";

Just start removing spaces while you walk through the string;
whenever you see a '"' suspend the space removal and when you
see another '"' resume it. Don't forget to stop at the end of
the string.

Ralf
Sep 19 '07 #2

P: n/a
"ramu" writes:
Suppose I have a string like this:

"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"

In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?
Set a flag indicating you have encountered the first delimiter. Think of one
or more _states_. Search for information on modes and states and state
diagrams if you still have trouble.
Sep 19 '07 #3

P: n/a
On Sep 19, 12:16 pm, "osmium" <r124c4u...@comcast.netwrote:
"ramu" writes:
Suppose I have a string like this:
"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?

Set a flag indicating you have encountered the first delimiter. Think of one
or more _states_. Search for information on modes and states and state
diagrams if you still have trouble.
I have done like this:
char *strrmspace (char *s )
{
char *sptr = s;
char *instr = s;
char *outstr;
int i = 0;
boolean found_quote = FALSE;

outstr = (char * )malloc(strlen(s)+1);

while ( *instr != '\0')
{
if ( found_quote )
{
outstr[i++] = *instr;
}
else
{
if ( !isspace( *instr) )
{
outstr[i++] = *instr;
}
}

if (( *instr == '"') && ( instr[-1] != '\\'))
{
found_quote = !found_quote;
}
instr++;
} /* while */
outstr[i] = '\0';
(void)strcpy(s, outstr);
free (outstr);
return(sptr);
} /* strrmspace */

And if I have a string

char s[] = "I have a string \"\\\" I want to remove space in this
string but not in the \"inner string\" ";

But this is removing spaces in \"inner string\" when there is
backslash in the previous inner string ie. \"\\\".
I don't want to remove the spaces in the inner strings. How can I
achieve this?

regards
Sep 19 '07 #4

P: n/a
In article <11**********************@22g2000hsm.googlegroups. com>,
ramu <ra******@gmail.comwrote:
>Suppose I have a string like this:
>"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
>In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?
Incomplete specification.
- Do inner strings nest?
- why is the ending delimeter for the inner string \\\" instead
of \" ? What should happen if a \" appears in the inner string?
--
Okay, buzzwords only. Two syllables, tops. -- Laurie Anderson
Sep 19 '07 #5

P: n/a
"ramu" wrote:
I have done like this:
char *strrmspace (char *s )
{
char *sptr = s;
char *instr = s;
char *outstr;
int i = 0;
boolean found_quote = FALSE;

outstr = (char * )malloc(strlen(s)+1);

while ( *instr != '\0')
{
if ( found_quote )
{
outstr[i++] = *instr;
}
else
{
if ( !isspace( *instr) )
{
outstr[i++] = *instr;
}
}

if (( *instr == '"') && ( instr[-1] != '\\'))
{
found_quote = !found_quote;
}
instr++;
} /* while */
outstr[i] = '\0';
(void)strcpy(s, outstr);
free (outstr);
return(sptr);
} /* strrmspace */

And if I have a string

char s[] = "I have a string \"\\\" I want to remove space in this
string but not in the \"inner string\" ";
See, I don't know what the word this applies to. We are not communicating.
Furthermore, I don't *want* to know. You have to have rigorous definitions
to have conversations such as the one you are attempting.
But this is removing spaces in \"inner string\" when there is
backslash in the previous inner string ie. \"\\\".
I don't want to remove the spaces in the inner strings. How can I
achieve this?
The link is not very good but it might help. This is a very simple thing
but it is almost impossible to describe without the ability to make
drawings. You have states and there are certain characters, sometimes
called terminals, that change the state, perhaps the quote or left slash in
your example. Or perhaps both, I didn't try to follow the details of what
you want. You can have an unlimited number of states. There is no
requirement for any kind of symmetry in a state diagram, simple examples
might give you that impression. You might also look up meta-language. I
think you are using quote and left backslash as a meta language in your
posts.
http://en.wikipedia.org/wiki/State_diagram
Sep 19 '07 #6

P: n/a

"ramu" <ra******@gmail.comwrote in message
news:11**********************@k79g2000hse.googlegr oups.com...
On Sep 19, 12:16 pm, "osmium" <r124c4u...@comcast.netwrote:
>"ramu" writes:
Suppose I have a string like this:
"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?

Set a flag indicating you have encountered the first delimiter. Think of
one
or more _states_. Search for information on modes and states and state
diagrams if you still have trouble.

I have done like this:
char *strrmspace (char *s )
{
char *sptr = s;
char *instr = s;
char *outstr;
int i = 0;
boolean found_quote = FALSE;

outstr = (char * )malloc(strlen(s)+1);

while ( *instr != '\0')
{
if ( found_quote )
{
outstr[i++] = *instr;
}
else
{
if ( !isspace( *instr) )
{
outstr[i++] = *instr;
}
}

if (( *instr == '"') && ( instr[-1] != '\\'))
{
found_quote = !found_quote;
}
instr++;
} /* while */
outstr[i] = '\0';
(void)strcpy(s, outstr);
free (outstr);
return(sptr);
} /* strrmspace */

And if I have a string

char s[] = "I have a string \"\\\" I want to remove space in this
string but not in the \"inner string\" ";

But this is removing spaces in \"inner string\" when there is
backslash in the previous inner string ie. \"\\\".
I don't want to remove the spaces in the inner strings. How can I
achieve this?

regards

When you encounter a quote, check the previous character to see
whether that quote is escaped or not.
--
Fred L. Kleinschmidt
Boeing Associate Technical Fellow
Aero Stability and Controls Computing
Sep 19 '07 #7

P: n/a
On Sep 19, 2:13 pm, rober...@ibd.nrc-cnrc.gc.ca (Walter Roberson)
wrote:
In article <1190217378.900611.188...@22g2000hsm.googlegroups. com>,

ramu <ramu....@gmail.comwrote:
Suppose I have a string like this:
"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?

Incomplete specification.
- Do inner strings nest?
- why is the ending delimeter for the inner string \\\" instead
of \" ? What should happen if a \" appears in the inner string?
--
Okay, buzzwords only. Two syllables, tops. -- Laurie Anderson
No. inner strings do not nest. But inner strings can contain one or
more double quote and/or one or more back slash.
The delimiter is double quote and \\ is the part of the inner
string.

The user input might be like this:

"I have a string "\\" I want to remove space in
this "string but not in the" "\"" inner string"

Regards

Sep 19 '07 #8

P: n/a
On Wed, 19 Sep 2007 08:56:18 -0700, ramu wrote:
Hi,

Suppose I have a string like this:

"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"

In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?
Use a status variable, initialized to (e.g. 0). Loop through the
source. If a character is whitespace, copy it only if the status
is 0. If it is a quotation mark, toggle the status, and copy it
to the target. Else, copy it to the target. A switch statement in
a loop will do that.
--
Army1987 (Replace "NOSPAM" with "email")
If you're sending e-mail from a Windows machine, turn off Microsoft's
stupid “Smart Quotes” feature. This is so you'll avoid sprinkling garbage
characters through your mail. -- Eric S. Raymond and Rick Moen

Sep 19 '07 #9

P: n/a
On Wed, 19 Sep 2007 09:53:54 -0700, ramu <ra******@gmail.comwrote:
>On Sep 19, 12:16 pm, "osmium" <r124c4u...@comcast.netwrote:
>"ramu" writes:
Suppose I have a string like this:
"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?

Set a flag indicating you have encountered the first delimiter. Think of one
or more _states_. Search for information on modes and states and state
diagrams if you still have trouble.

I have done like this:
Not a bad first effort.
>char *strrmspace (char *s )
Unfortunately, you have chosen a reserved name for your function.
>{
char *sptr = s;
char *instr = s;
char *outstr;
int i = 0;
boolean found_quote = FALSE;

outstr = (char * )malloc(strlen(s)+1);
Don't cast the return from malloc. It can never help but can lead to
silencing a diagnostic you would really want to see.
>
while ( *instr != '\0')
{
if ( found_quote )
{
outstr[i++] = *instr;
}
else
{
if ( !isspace( *instr) )
isspace returns true for characters other than ' '.
{
outstr[i++] = *instr;
}
}

if (( *instr == '"') && ( instr[-1] != '\\'))
This will cause undefined behavior if a " is the first character of
the input string.
{
found_quote = !found_quote;
}
instr++;
} /* while */
outstr[i] = '\0';
(void)strcpy(s, outstr);
Why the cast?
free (outstr);
return(sptr);
sptr was set to s and neither was ever modified. It looks like you
don't need sptr and can return s. return is a statement, not a
function; the parentheses are unnecessary.
>} /* strrmspace */

And if I have a string

char s[] = "I have a string \"\\\" I want to remove space in this
string but not in the \"inner string\" ";

But this is removing spaces in \"inner string\" when there is
backslash in the previous inner string ie. \"\\\".
I don't want to remove the spaces in the inner strings. How can I
achieve this?
It would avoid ambiguity if you would specify the desired output after
processing the above array and show us the output your function is
producing.

One problem you may think you have is that the \" you see after the
first word string is not two characters at execution time. It is
acutely the start of your inner string which continues until the \"
before the word inner. The phrase inner string is part of your outer
string and should be stripped.
Remove del for email
Sep 20 '07 #10

P: n/a

"ramu" <ra******@gmail.comwrote in message
news:11**********************@22g2000hsm.googlegro ups.com...
Hi,

Suppose I have a string like this:

"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"

In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?
If you still haven't found a solution, please write:

1) A sample string, as typed by the user.
2) The same string, according to the C syntax.
3) The processed string, in C syntax.
4) The processed string, as written to the console.

Do you confirm that the START of the *inner string*
is marked by \" ?

Do you confirm that the END of the *inner string*
is marked by \" ?

Or what?

Sep 20 '07 #11

P: n/a
ramu wrote:
On Sep 19, 2:13 pm, rober...@ibd.nrc-cnrc.gc.ca (Walter Roberson)
wrote:
>In article <1190217378.900611.188...@22g2000hsm.googlegroups. com>,

ramu <ramu....@gmail.comwrote:
>>Suppose I have a string like this:
"I have a string \"and a inner string\\\" I want to remove space in
this string but not in the inner string"
In the above string I have to remove spaces, but not in the inner
string(\"and a inner string\\\"). Will anyone please tell me how to do
this?
Incomplete specification.
- Do inner strings nest?
- why is the ending delimeter for the inner string \\\" instead
of \" ? What should happen if a \" appears in the inner string?
--
Okay, buzzwords only. Two syllables, tops. -- Laurie Anderson

No. inner strings do not nest. But inner strings can contain one or
more double quote and/or one or more back slash.
The delimiter is double quote and \\ is the part of the inner
string.

The user input might be like this:

"I have a string "\\" I want to remove space in
this "string but not in the" "\"" inner string"
I assume that an inner string has the same syntax as a C string literal.
If not, please show exactly how they differ. If so, then the inner
string may represent \ and " characters by escaping them with the
sequences \\ and \". It is important to note that within string
literals a series of \s are paired:
"\\\\"
is a string literal containing \\, not the beginning of one containing
an escaped quote.

I try here to separate the actual characters in an array with the
representation as a string literal.

Start with
<string>the "bad" boys</string>
having 14 characters, where <stringand </stringare the delimiters of
a sequence of characters (to reduce confusion).

C string literal (which is a string of characters) containing those
characters:
<string>"the \"bad\" boys"</string>
has 18 characters.

A character string containing the above string literal:
<string>I saw "the \"bad\" boys" yesterday.</string>

If you give that string as input to your program, I assume you want the
output to be
<string>Isaw"the \"bad\" boys"yesterday.</string>,
but without the outside delimiters.

You could read the input string shown above, without the outside
delimiters, from an input stream.

If you wanted to represent the input as a string literal for testing,
you would code
char s[] = "I saw \"the \\\"bad\\\" boys\" yesterday.";

Your earlier example:
char s[] = "I have a string \"\\\" I want to remove space in this
string but not in the \"inner string\" ";

is a representation of the character sequence
<string>I have a string "\" I want to remove space in this
string but not in the "inner string" </string>

Using my assumed definition of inner string, the inner strings are
<string>\" I want to remove space in this string but not in the </string>
and the unterminated inner string
<string</string>
at the very end of the subject string.

Is that what you intend?

--
Thad
Sep 21 '07 #12

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