C++ Primer 习题3.8

#include <string>
#include <iostream>
using std::cin;
using std::cout;
using std::endl;
using std::string;
using std::cerr;
int main()
{
int states = 0;
string result = "";
do{
cout<<"Make you choice!"<<endl<<"1 - input a string \n0 - end inputing strings "<<endl;
cin>>states;
if(states == 1){
cout<<"Input your string."<<endl;
cin>>temp;
result += temp;
}else if(states != 0 && states != 1){
cerr<<"error choice!!"<<endl;
}
}while (states != 0);
cout<<"The result of combing all the strings you input is "<<result<<endl;
system("pause");
return 0;
}