Re: C Containers Library vs STL

Ian Collins <>
Thu, 04 Aug 2011 09:13:08 +1200
On 08/ 4/11 08:40 AM, jacob navia wrote:


I would like to compare the C containers library (written in C for C
programmers) against the STL.

Here is the code for the CCL. Maybe one C++ wizard would solve the
same problem using the STL?

I would be very ingterested in comparing code size, complexity, etc.

Thanks in advance, and here is the C part:

Given a text file, print in standard output the lines that are
unique in it, i.e. filtering all duplicated lines.


Normally this involves keeping a sorted list/array of lines
and testing if a line is in the set or not.

Solution using the CCL.

    1 #include<containers.h>
    2 int main(int argc,char *argv[])
    3 {
    4 FILE *f;
    5 int i=1,r;
    6 Dictionary *dict;
    7 char buf[8192];
    9 if (argc< 2) {
   10 fprintf(stderr,"%s<file name>\n",argv[0]);
   11 return -1;
   12 }
   13 f = fopen(argv[1],"r");
   14 if (f == NULL)
   15 return -1;
   16 dict = iDictionary.Create(0,500);
   17 if (dict == NULL)
   18 return -1;
   19 while (fgets(buf,sizeof(buf),f)) {
   20 r= iDictionary.Add(dict,buf,NULL);
   21 if (r> 0)
   22 printf("[%3d] %s",i,buf);
   23 else if (r< 0) break;
   24 i++;
   25 }
   26 iDictionary.Finalize(dict);
   27 fclose(f);
   28 }

A hash table will be used to determine if a line is a duplicate
or not.

This is probably the closest equivalent (sticking to a similar layout

#include <set>
#include <string>
#include <iostream>
#include <fstream>

typedef std::set<std::string> Lines;

int main( int argc, char** argv )
   std::ifstream in( argv[1] );

   Lines unique;

   while( in ) {
     std::string line;

     std::getline( in, line );

     if( unique.insert(line).second ) {
       std::cout << line << std::endl;

We use the following local variables (lines 4-7):
Name Usage
f Input stream bound to the file to read
i Counter for lines read
r Result of adding a line
dict Dictionary (Hash table)
buf Line buffer limited to 8K per line

It would have been much easier to give the variables meaningful names!

Ian Collins

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