宏条件编译

//在vs2008下编译通过

#include <iostream>#include<fstream>#ifndef OPTION_LONG//预处理定义#define OPTION_LONG 1#define OPTION_DETAILED 0#endifstatic int print_ledger_long(int rhs)//定义条件函数{    std::cout<<rhs<<std::endl;    return rhs;}int main(int argc, char* argv[]){#if OPTION_LONG//条件编译    print_ledger_long(5);#elif     print_ledger_long(4);#endif//条件编译结束    system("pause");    return 0;}