Programming

I have string named texts which consist of section label “BOOK-SEC-“. Section starts from 1 to n, where n is a number. For this example conside the value of n is 9. That is, the string variable looks like
“BOOK-SEC-1 blablgjfsdgdflgfablablablablaBOOK-SEC-2blablablabalasdfsdhfhBOOK-SEC-3blajgfyasdasdfgdagfblablaBOOK-SEC-4blablajahdu.....styadhsabfdaskfBOOK-SEC-9blablaahdfgablaz".
The data following the BOOK-SEC-1 belongs to section 1, the data following the BOOK-SEC-2 belongs to section 2 and so on.
See the below code:
#include<iostream>
#include<sstream>
using namespace std;
const std::string SECTION_LABEL ("BOOK-SEC-");
static unsigned int getNumberSections (const std::string &texts );
int main ()
{
string texts;
texts = "BOOK-SEC-1blablgjfsdgdflgfablablablablaBOOK-SEC-2blablablabalasdfsdhfhBOOK-SEC-3blajgfyasdasdfgdagfblablaBOOK-SEC\
-4blablaj......ahdustyadhsabfdaskfBOOK-SEC-9blablaahdfgablaz";
unsigned int number;
number = getNumberSections(texts);
cout<<"\n the number is: "<<number<<endl;
return 0;
}
unsigned int getNumberSections (const string & texts)
{
string::size_type pos = texts.rfind (SECTION_LABEL);
pos += SECTION_LABEL.length ();
string numberAsText;
while (isdigit (texts[pos]))
{
numberAsText.push_back (texts[pos]);
++pos;
}
return atoi (numberAsText.c_str ());
}

This gives the correct output: the number is: 9

The problem when the string looks like:
string texts;
texts = "BOOK-SEC-1blablgjfsdgdflgfablablablablaBOOK-SEC-2blablablabalasdfsdhfhBOOK-SEC-3blajgfyasdasdfgdagfblablaBOOK-SEC\
-4blablaj......ahdustyadhsabfdaskfBOOK-SEC-99blablaahdfgablaz";

check the part "BOOK-SEC-99blablaahdfgablaz. Here section is 9 and another 9 is the data of that section.
For this string I get the output as
the number is: 99
which is wrong.

please suggest a solution to get the correct value.

Note: In any case we should not alter the SECTION_LABEL or to distrub the string variable.

This sick command could do the trick

Code:

sed 's/BOOK/\nBOOK/g' youfile.txt | sed 's/BOOK-SEC-\([1-9]\).*/\1/g'

There must be smarter way to do that but i didn't find out yet.

As I noticed the text "BOOK-SEC-" is fixed and occurring again and again, what you can do is :: Search the pattern "BOOK-SEC-" in your string then read one byte. Also maintain count in your string and check the end of string.