You do not need to program string manipulation as it is already part of the standard library. See std::string and std::wstring.
You can perform arithmetic with it. int x {42}; x *= 2; // ok std::string s {"Hello"}; s *= 2; // error: std::string::operator*= (int) is undefined
C++ already provides a string class in the C++ standard template library. #include<iostream> #include<string> int main() { using namespace std; string s {"Hello world!"}; cout << s << endl; }
std::string input = ""; std::getline (std::cin, input); // get input from stdin std::stringstream ss (input); // place input in a string stream integer num = 0; if (ss >> num) // extract integer from string stream { // Success! } else { // Fail! }
Use the following function to count the number of digits in a string. size_t count_digits (const std::string& str) { size_t count = 0; for (std::string::const_iterator it=str.begin(); it!=str.end(); ++it) { const char& c = *it; if (c>='0' && c<='9'); ++count; } return count; }
std::string::substr();
strcpy
No.
You can perform arithmetic with it. int x {42}; x *= 2; // ok std::string s {"Hello"}; s *= 2; // error: std::string::operator*= (int) is undefined
C++ already provides a string class in the C++ standard template library. #include<iostream> #include<string> int main() { using namespace std; string s {"Hello world!"}; cout << s << endl; }
#include <iostream> #include <string> int main() { std::string myStr = ""; std::cout << std::endl << "Enter a string: "; std::cin >> myStr; system("PAUSE"); return 0; }
Use the following function to count the number of digits in a string. size_t count_digits (const std::string& str) { size_t count = 0; for (std::string::const_iterator it=str.begin(); it!=str.end(); ++it) { const char& c = *it; if (c>='0' && c<='9'); ++count; } return count; }
std::string input = ""; std::getline (std::cin, input); // get input from stdin std::stringstream ss (input); // place input in a string stream integer num = 0; if (ss >> num) // extract integer from string stream { // Success! } else { // Fail! }
std::string::substr();
Nothing.The C language only recognizes a few keywords, like "for" and "if". Most of what's in a C program ... that doesn't reference routines in the C program itself ... are library calls, and cputs() is one of those. What it does is write its argument (which should be a pointer to a character string) to the console... console put string.
#include<iostream> #include<string> int main() { std::string s("The quick brown fox jumps over the lazy dog"); std::cout<<s.c_str()<<std::endl; std::cout<<"The previous string is "<<s.size()<<" characters long."<<std::endl; }
To swap two variables without using a third variable, use exclusive or manipulation... a ^= b; b ^= a; a ^= b;
You don't need a program to compare strings since std::string already provides support for all the comparison operators (<, <=, >, >=, == and !=). To roll your own you must first create a string class and then provide operator overloads for the comparison operators. To compare strings, start at the first character in each string and compare. So long as they remain equal, move onto the next character. The comparison ends as soon as any character differs. You need only compare these two characters to decide which string is the lesser. To perform a case insensitive comparison, copy the two characters and convert the copies to lower case (or upper case, it doesn't matter). Then compare the copies. Do this for each character as you compare them rather than converting the entire string.
#include<iostream> #include<vector> #include<string> int main() { std::vector<std::string> names; for (int loop=0; loop!=10;) { std::cout << ++loop << " enter a name: "; std::string name; std::cin >> name; names.push_back (name); } }
The plus operator between string constants allows string concatination: string a = "Hello, "; string b = "World!"; string c = a + b; The output of c would be: "Hello, World!".
Yes.
#include<list> #include<string> struct Customer { std::string m_name; std::string m_phone; Customer (std::string name, std::string phone): m_name(name), m_phone(phone) {} // ... }; int main() { std::list<Customer> customers; customers.push_back ("Joe Bloggs", "555 7465"); customers.push_back ("Dan Mann", "555 3458"); // ... }
#include<iostream> #include<vector> #include<string> struct employee { std::string forename; std::string surname; std::string department; }; struct directory { std::vector<employee> v; void add_employee (const std::string&, const std::string&, const std::string&); }; void directory::add_employee (const std::string& forename, const std::string& surname, const std::string& department) { v.push_back (employee{forename, surname, department}); } int main() { std::string forename, surname, department; std::cout << "Enter employee's forename: "; std::cin >> forename; std::cout << "Enter employee's surname: "; std::cin >> surname; std::cout << "Enter employee's department: "; std::cin >> department; add_employee (forename, surname, department); }
A std::string is an object that encapsulates an array of type char whereas a C-style string is a primitive array with no members. A std::string is guaranteed to be null-terminated but a C-style string is not.
It means that you press the Ctrl key and holding it down, press the F1 key to perform a certain function on a personal computer and the function you perform depends on the context and the program running etc.
You can use "string" class in C++ for string operations or you may use c style string functions as well. #include <string> String class in C++ provides all basic function to operate on strings. you may details descriptin at http://www.cplusplus.com/reference/string/string/