c++ file parser slow compared to c# -

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i need write file parser in c++.

here's code : 

std::string line;        vector<string> slice;  while(getline(m_inputstream, line))   {            }

my file big, loop takes 12 seconds.

my c# code : 

streamreader sr = new streamreader(filename); string strline = "";  while (!sr.endofstream) {     strline = sr.readline(); }

and takes 0.6 seconds... doing wrong in c++?

firstly, doing slice?

chances c# version reading string discarding - , c# jit optimising no-op, 0.6 seconds takes initialise , quit. c++ version generate code read string processing input file. make sure c++ 1 built release settings if you're going compare performance, debug code meaningless perf.

do string , you'll see different performance figures, , check memory usage in both systems, c# 1 use lot more ram until gc kicks in.


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