鲁达 有文件cad.dat，其内容如下：
C is one of the world's most modern
programming languages. There is no
language as versatile as C, and C
is fun to use.
现在的任务是，读取以上文件的内容，并将其中的字符“C“替换为“C++“并写入文件。
#include <fstream> #include <iostream> #include <cstdlib> using namespace std; void addPlusPlus(ifstream& inStream, ofstream& outStream); int main( ) { ifstream fin; ofstream fout; cout << "Begin editing files.\n"; ("cad.dat"); if ( )) { cout << "Input file opening failed.\n"; exit(1); } ("c;); if ( )) { cout << "Output file opening failed.\n"; exit(1); } addPlusPlus(fin, fout); ( ); ( ); cout << "End of editing files.\n"; return 0; } void addPlusPlus(ifstream& inStream, ofstream& outStream) { char next; inS(next);//从文件读取一个字符给next while (! inS( )) { if (next == 'C') outStream << "C++";//输出字面常量给文件 else outStream << next;//输出变量next值给文件 inS(next); } }以上程序运行后，会在当前目录下自动新建一文件c，其内容如下：
C++ is one of the world's most modern programming languages. There is no language as versatile as C++, and C++ is fun to use.－End－