How do you create file with a variable in C++?

Question

I was wondering how to put a variable where "example.txt" is below:

ofstream file;
file.open ("example.txt");

Answer 1

just put a variable there :-P

if you use std::string then you need to get the const char* using .c_str() so your options are:

const char *filename = "example.txt"
file.open(filename);

or:

std::string filename = "example.txt"
file.open(filename.c_str());