#include <iostream> #include <fstream> using namespace std; int main() { ofstream fout("test.dat"); if(!fout) { cout << "Cannot open file.\n"; return 1; } fout << 10 << " " << -20 << " " << 30.2 << "\n"; fout << "This is a test."; fout.close(); if(!fout.good()) { cout << "A file error occurred."; return 1; } }