read file & substring with C++

Probably the fastest way to do it would be to use low level IO (open/read or fopen/fread). However, with a program this small it's unlikely that compile time will be significantly different whichever version you choose. You can find the references to the above functions quite easily; I would post a Google link but you told us not to.

You'd need to do some trial/error here. Create a few different code snippets. Then try them each with different compilers. Then pick the compiler/code combination that gives you the best compile-time. The machine itself probably won't matter since your code will be small enough that multiple CPUs won't help much. But running the compiler and the source file off an SSD or even a RAM-drive will further boost speeds.

Weird contest though, since the compiler's speed has nothing to do with your ability as a coder.

i find out that is the optimal solution is:

ifstream myReadFile;
 myReadFile.open("text.txt");
 char output[100];
 if (myReadFile.is_open()) {
 while (!myReadFile.eof()) {


    myReadFile >> output;
    cout<<output;


 }
}
myReadFile.close();

thanks everybody