Iterator
An iterator is any object that, pointing to some element in a range of elements (such as an array or a container), has the ability to iterate through the elements of that range.
Syntax
type_container :: iterator var_name;
Example
The below example demonstrates the use of iterators.
C++
// C++ program to demonstrate iterators #include <iostream> #include <vector> using namespace std; int main() { // Declaring a vector vector<int> v = { 1, 2, 3 }; // Declaring an iterator vector<int>::iterator i; int j; cout << "Without iterators = "; // Accessing the elements without using iterators for (j = 0; j < 3; ++j) { cout << v[j] << " "; } cout << "\nWith iterators = "; // Accessing the elements using iterators for (i = v.begin(); i != v.end(); ++i) { cout << *i << " "; } // Adding one more element to vector v.push_back(4); cout << "\nWithout iterators = "; // Accessing the elements without using iterators for (j = 0; j < 4; ++j) { cout << v[j] << " "; } cout << "\nWith iterators = "; // Accessing the elements using iterators for (i = v.begin(); i != v.end(); ++i) { cout << *i << " "; } return 0; } |
Output
Without iterators = 1 2 3 With iterators = 1 2 3 Without iterators = 1 2 3 4 With iterators = 1 2 3 4
Difference between Iterators and Pointers in C++ with Examples
In C++ programming, we have both pointers and iterators that are used in managing and manipulating data structures. There are many similarities between iterators and pointers in their ability to reference and dereference memory, but there are certain differences between the two. Understanding the difference is very important in C++ programming.