#include <sstream> #include <fstream> #include <string> using namespace std; string itos(int i){ stringstream s; s << i; return s.str(); } int main(){ string fname = "file", ext = ".txt"; int someNum = 10; for (int i=0; i<someNum; i++){ fname += itos(i) + ext; ofstream out(fname.c_str()); out.close(); fname = fname.substr(0,4); } return 0; }