C++ : Reading file and store data in multi-vector

I am trying to read data file with this format:

T1: I1,I2,I5
T2: I2,I4
T3: I2,I3
T4: I1,I2,I4
T5: I1,I3
T6: I2,I3
T7: I1,I3
T8: I1,I2,I3,I5
T9: I1,I2,I3

I don't want to read the first column T1,T2,T3 ...... , but each line will be a dataset I want to start read after (space '  ' ) and end with each line and how can I separate the data according to (comma ',')

I wrote this code but it didn't work correctly and it reads the first column anyway

string CItem;

// set of elements
set< CItem > CItemSet;

 CItemSet CTransaction;

// set of transactions
vector< CTransaction > CTransactionSet;

ifstream inFile(inFileName);
	if (!inFile)
		cout << "Failed to open input file filename:." << inFileName;

CTransactionSet transSet;
	CTransaction tran;
	string txtLine;
	// read every line from the stream
	while (getline(inFile, txtLine))
		istringstream txtStream(txtLine);
		string txtElement;
		// read every element from the line that is seperated by commas
		// and put it into the vector or strings
		while (getline(txtStream, txtElement, ','))
			if (txtElement == ": ") break;
			else tran.insert(txtElement);

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Karrtik IyerSoftware ArchitectCommented:
I suggest you simply do a get line first to read entire lines as in the file, then perform string operations to get the required data.
1) read  entire line, so you will get 4-5 strings (number of rows)
2) then perform substring to remove T1,T2 part..
3) the perform string split with comma as the separator to get the individual values.
Karrtik IyerSoftware ArchitectCommented:
Your below line of code :
while (getline(txtStream, txtElement, ','))
Shall return T1: I1
So your if condition shall never succeed to break (one more thing ideally instead of break you should do continue since you want other data in the row), the string shall never match to be only ":"
Hence you shall always get T1 as well in your vector which you wanted to skip...
AaeshahAuthor Commented:
Could you please show me an example how to perform substring to remove T1,T2 part..
and how to split them in a code, Please!
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Karrtik IyerSoftware ArchitectCommented:
Try this sample, please let me know if something is not clear
  std::ifstream ifs ("test.txt", std::ifstream::in);//Read the file in input mode
  string eachline;
  while(getline(ifs,eachline)){//Read each line into a string
    if(!ifs.good())//if it (file state) is no more valid break and close the file
    stringstream txtStream(eachline);//Insert the string to string stream for further processing
    txtStream.ignore(eachline.length(),':');// Ignore the T1: part since we are not interested in it
    std::string token;//to contain each element that we are interested in
    while(std::getline(txtStream, token, ',')) {//Get elements seperated by comma into the token variable.
        std::cout << token << ',';// This token might still contain white spaces
    //You can read this token and insert into your vector
    std::cout << endl;//Insert new line
  ifs.close();//Close the file stream handle

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Karrtik IyerSoftware ArchitectCommented:
Also as a better optimization I suggested to keep the file handle open for as less time as possible in case if it is a shared resource. If it involves pretty straightforward and small amount of string processing it might still not create any problems. But if you plan to do more string processing and formatting after reading each line and if file can contain lot of records then  it would be ideal that you read the entire file into a string. And the perform all the string processing and formatting in memory without keeping the file handle open for the entire time when string processing is done. It depends on how the file is updated by other clients...
Hope it is clear.
AaeshahAuthor Commented:
Thank you very much that solve my problem using .ignore is all I need. Thanks again
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