Re: STL::MAP: Printing values only once ..

From:

Ian Collins <ian-news@hotmail.com>

Newsgroups:

comp.lang.c++

Date:

Sat, 18 Jan 2014 15:53:57 +1300

Message-ID:

<bju8m5F4b9tU3@mid.individual.net>

Rahul Mathur wrote:

Hi,

I have a input.txt file separator by pipe '|' as -

40147|181|ORANGE|MIKE|XX||1000397900|3500
40148|373|ORANGE|BOB|XX||1078889400|4500
40149|673|ORANGE|TREY|XX||1095159900|5500

I only wish to have all the FIRST(ID=40147) and LAST FIELD(PRICE=3500) to be printed for three lines as given above.

I am reading as -

--
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <boost/algorithm/string.hpp>

using namespace std;

struct FILE_INPUT {
         int ID;
         int Asset_ID;
         char T_Name[];

You really shouldn't be using a zero size array here, it isn't valid C++
and certainly isn't what you want.

         char Symbol[];
         char Series[];
         char Gap;
         int Date;
         int price;
};

int main() {

         typedef std::map<int, int> unordmap;

Not a very good name for a std::map, which is ordered!

         unordmap ask;

         FILE_INPUT fl_inp;
         memset( &fl_inp, 0, sizeof(fl_inp) );
         ifstream in ("input.txt");
         string s;

         const char delimiter = '|';
         while ( getline (in, s) ) {
         trim( s );

Missing namespace?

         if ( !s.empty() ) {
                 stringstream strm( s );
                 string item;
                 getline( strm, item );
                 stringstream stra( item );
                 string tmp;
                 getline( stra, tmp, delimiter );
                 {
                        stringstream strb( tmp );
                        strb >> fl_inp.ID;
                 }
                 getline( stra, tmp, delimiter )

Missing semicolon.

                 {
                        stringstream strb( tmp );
                        strb >> fl_inp.price;
                 }

                 ask.insert( std::make_pair((fl_inp.ID),(fl_inp.price)) );

This next section shouldn't be inside the while loop! You are printing
the map each time you add to it.

                 unordmap::iterator pos = ask.begin();
                 for (pos = ask.begin(); pos != ask.end(); ++pos) {
                         std::cout << "ID: " << pos->first << "\t"
                         << "Price: " << pos->second << std::endl;
                 }
                 std::cout << " " << endl;

To here.

}
}
}

--
Ian Collins