书中页数：P287 代码名称：sstream.cc
#include <iostream> using std::cin; using std::cout; using std::cerr; using std::istream; using std::ostream; using std::endl; #include <sstream> using std::ostringstream; using std::istringstream; #include <vector> using std::vector; #include <string> using std::string; // members are public by default struct PersonInfo { string name; vector<string> phones; }; // we'll see how to reformat phone numbers in chapter 17 // for now just return the string we're given string format(const string &s) { return s; } bool valid(const string &s) { // we'll see how to validate phone numbers // in chapter 17, for now just return true return true; } vector<PersonInfo> getData(istream &is) { // will hold a line and word from input, respectively string line, word; // will hold all the records from the input vector<PersonInfo> people; // read the input a line at a time until end-of-file (or other error) while (getline(is, line)) { PersonInfo info; // object to hold this record's data istringstream record(line); // bind record to the line we just read record >> info.name; // read the name while (record >> word) // read the phone numbers info.phones.push_back(word); // and store them people.push_back(info); // append this record to people } return people; } ostream& process(ostream &os, vector<PersonInfo> people) { for (const auto &entry : people) { // for each entry in people ostringstream formatted, badNums; // objects created on each loop for (const auto &nums : entry.phones) { // for each number if (!valid(nums)) { badNums << " " << nums; // string in badNums } else // ``writes'' to formatted's string formatted << " " << format(nums); } if (badNums.str().empty()) // there were no bad numbers os << entry.name << " " // print the name << formatted.str() << endl; // and reformatted numbers else // otherwise, print the name and bad numbers cerr << "input error: " << entry.name << " invalid number(s) " << badNums.str() << endl; } return os; } int main() { process(cout, getData(cin)); return 0; }