C++ Tutorial/string/string read

Read a string from keyboard and decide if to exit a while loop

<source lang="cpp">#include <iostream>

1. include <string>

using namespace std; class Product { public:

  Product();
  void read();
  bool is_better_than(Product b) const;
  void print() const;

private:

  string name;
  double price;
  int score;

}; Product::Product() {

  price = 1;
  score = 0;

} void Product::read() {

  cout << "Please enter the model name: ";
  getline(cin, name);
  cout << "Please enter the price: ";
  cin >> price;
  cout << "Please enter the score: ";
  cin >> score;
  string remainder; /* read remainder of line */
  getline(cin, remainder);

} bool Product::is_better_than(Product b) const {

  if (b.price == 0) return false;
  if (price == 0) return true;
  return score / price > b.score / b.price;

} void Product::print() const {

  cout << name
     << " Price: " << price
     << " Score: " << score << "\n";

} int main() {

  Product best;
  bool more = true;
  while (more)
  {  
     Product next;
     next.read();
     if (next.is_better_than(best)) best = next;
     cout << "More data? (y/n) ";
     string answer;
     getline(cin, answer);
     if (answer != "y") more = false;
  }
  cout << "The best value is ";
  best.print();
  return 0;

}</source>

Read string from keyboard and get substring

<source lang="cpp">#include <iostream>

1. include <string>

using namespace std; int main() {

  cout << "Enter your full name (first middle last): ";
  string first;
  string middle;
  string last;
  cin >> first >> middle >> last;
  string initials = first.substr(0, 1) + middle.substr(0, 1) + last.substr(0, 1);
  cout << "Your initials are " << initials << "\n";
  return 0;

}</source>

Read string till a sign

<source lang="cpp">#include <iostream>

 #include <string>    
 using namespace std;  
   
 int main(){
    string full_name, nickname, address;  
    string greeting("Hello, ");  
   
    cout << "Enter your full name: ";  
    getline(cin, full_name);     
    cout << "Your full name is: " << full_name << endl;  
   
    cout << "Enter your nickname: ";  
    cin >> nickname;             
   
    greeting += nickname;        
    cout << greeting << endl;    
   
    cout << "Enter your address on separate lines\n";  
    cout << "Terminate with "$"\n";  
    getline(cin, address, "$");
    cout << "Your address is: " << address << endl;  
    return 0;  
 }</source>

Use cin in while loop to read string

<source lang="cpp">#include <iostream>

1. include <string>

using namespace std; int main() {

  int count = 0;
  string word;
  while (cin >> word)
  {  
     count++;
  }
  cout << count << " words.\n";
  return 0;

}</source>

Use cin to read string

<source lang="cpp">#include <iostream> using std::cout; using std::endl; using std::cin; using std::boolalpha;

1. include <string>

using std::string; void display( const string & ); int main() {

  string string1;

  cout << "Statistics before input:\n" << boolalpha;
  display( string1 );
  cout << "\n\nEnter a string: ";
  cin >> string1; // delimited by whitespace
  cout << "The string entered was: " << string1;
  cout << "\nStatistics after input:\n";
  display( string1 );

  return 0;

} void display( const string &stringRef ) {

  cout << "capacity: " << stringRef.capacity() << "\nmax size: "  
     << stringRef.max_size() << "\nsize: " << stringRef.size()
     << "\nlength: " << stringRef.length() 
     << "\nempty: " << stringRef.empty();

}</source>

Statistics before input:
capacity: 0
max size: 1073741820
size: 0
length: 0
empty: true
Enter a string: a string
The string entered was: a
Statistics after input:
capacity: 1
max size: 1073741820
size: 1
length: 1
empty: false"