в 14:21, 25 мая 2010

2010-05-25T14:21:17Z

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2010-05-25T10:30:30Z

1 версия: Импорт контента...

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

<source lang="cpp">#include <iostream>
#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>
#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>
#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;
#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>
<pre class=codeResult>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"</pre>

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в 14:21, 25 мая 2010

Admin: 1 версия: Импорт контента...