Why is the inner loop for parsing the line I read being skipped every other iteration through the outter reading loop?

Question

#include <iostream>  
#include <iomanip>
#include <string>
#include <fstream>
#include <cmath>
#include <cstdlib>
#include <sstream>

using namespace std;

int main(int argc, char* argv[])
{;
    int arraylen = 7, arraylen_new = 0, i = 0, nextstep = 0;
    string line, field, junkText;
    string* randNum = new string[arraylen];
    string* phrase = new string[arraylen];

    ifstream randomTxt;
    arraylen = 5;

    randomTxt.open("random.txt");

    while(!randomTxt.eof())
    {
        getline(randomTxt,line);
        stringstream ss(line);
        nextstep = 0;
        while(getline(ss,field,','))
        {
            cout << i << endl;
            /*if(nextstep == 0)
            {
                randNum[i] = field;
                cout<< "number " << i << ": " << randNum[i] << endl;
                nextstep = 1;
            }

            else if(nextstep == 1)
            {
                junkText = field;
                cout<< "junk " << i << ": " << junkText << endl;
                nextstep = 2;               
            }
            else
            {
                items[i] = field;
                cout<< "items " << i << ": " << items[i] << endl;
            }*/

            if(i == (arraylen-1))
            {
                arraylen_new = arraylen + 1;
                string* temp1 = new string[arraylen_new];
                string* temp2 = new string[arraylen_new];
                copy(randNum, (randNum+arraylen), temp1);
                delete [] randNum;
                randNum = temp1;

                copy(phrase, (phrase + arraylen), temp2);
                delete [] phrase;
                phrase = temp2;
                arraylen = arraylen_new;
            }
        }
        cout<<"test"<<endl;
        i++;

    }    
    randomTxt.close();

    /*for(int i = 0; i < arraylen;i++)
    {
        cout<< "UPC " << i << ": " << UPC[i] << "\t" << "Phrase " << i << ": " << phrase[i] << endl;

    }*/

    return 0;
}

When checking the value for i the print out is as follows:

0
0
0
test
test
2
2
2
test
test
4
4
4

And so on until my file is read completely. My iteration needs to match up properly because I use it to save each piece of the line into separate arrays. Any ideas why it seems to skip the inner while loop?

Here is a snippet of the text file:

333331234567,blah,"this is nonsense"
222221234567,word,"yadda yadda words"
111111234567,thing,"total gibberish stuff"

Answer 1

I don't reproduce your issue.

But I had to fix some names in your sample code, so maybe I accidentally fixed it?

Here's my version, with some additional DEBUG print statements.

Also note that checking for eof() is rarely useful, so changed the outer loop to while (getline(randomTxt, line)).

Then with the i loop index, it's more natural to write as a for loop, I think.

Live On Coliru

#include <iostream>
#include <string>
#include <fstream>
#include <sstream>

/// returns: new array length

int main() {
    size_t arraylen = 7;
    std::string line;
    std::string *randNum = new std::string[arraylen];
    std::string *phrase  = new std::string[arraylen];

    std::ifstream randomTxt;

    randomTxt.open("random.txt");

    for (size_t i=0; getline(randomTxt, line); ++i)
    {
        std::cout << "DEBUG LINE: '" << line << "'\n";
        //nextstep = 0;

        std::stringstream ss(line);
        std::string field;
        while (getline(ss, field, ',')) {
            std::cout << "DEBUG INNER " << i << " '" << field << "'\n";

            if (i == (arraylen - 1)) {
                size_t arraylen_new = arraylen + 1;
                {
                    std::string *tmp = new std::string[arraylen_new];
                    copy(randNum, randNum + arraylen, tmp);
                    delete[] randNum;
                    randNum = tmp;
                }

                {
                    std::string *tmp = new std::string[arraylen_new];
                    copy(phrase, (phrase + arraylen), tmp);
                    delete[] phrase;
                    phrase = tmp;
                }
                arraylen = arraylen_new;
            }
        }
    }
}

Prints

DEBUG LINE: '333331234567,blah,"this is nonsense"'
DEBUG INNER 0 '333331234567'
DEBUG INNER 0 'blah'
DEBUG INNER 0 '"this is nonsense"'
DEBUG LINE: '222221234567,word,"yadda yadda words"'
DEBUG INNER 1 '222221234567'
DEBUG INNER 1 'word'
DEBUG INNER 1 '"yadda yadda words"'
DEBUG LINE: '111111234567,thing,"total gibberish stuff"'
DEBUG INNER 2 '111111234567'
DEBUG INNER 2 'thing'
DEBUG INNER 2 '"total gibberish stuff"'

Notes

• you may want make a grow_array function because you duplicated that code
• you may want to grow by factor instead of 1 element at a time; this won't scale at all and lead to abysmal performance/heap fragmentation