advance (STL Samples)
Illustrates how to use the advance Standard Template Library (STL) function in Visual C++.
template<class InIt, class Dist>
void advance(
InIt& it,
Dist n
);
Remarks
Notes
The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.
The advance STL function accepts two parameters:
InIt — The iterator to advance.
Dist — The number of elements to increment the iterator by.
The advance STL function advances the iterator n times. If the iterator is a random-access iterator type, the function evaluates the expression as iterator += n. Otherwise, it performs each increment by evaluating: ++iterator. If the iterator is an input or forward iterator type, n must not be negative.
Example
// Advance.cpp
// compile with: /EHsc
#pragma warning (disable:4786)
#include <iostream>
#include <string>
#include <list>
using namespace std ;
typedef list<string> STRLIST;
int main() {
STRLIST List;
STRLIST::iterator iList;
STRLIST::difference_type dTheDiff;
List.push_back("A1");
List.push_back("B2");
List.push_back("C3");
List.push_back("D4");
List.push_back("E5");
List.push_back("F6");
List.push_back("G7");
// Print out the list
iList=List.begin();
cout << "The list is: ";
for (int i = 0; i < 7 ; i++, iList++)
cout << *iList << " ";
// Initialize to the first element"
iList=List.begin();
cout << "\n\nAdvance to the 3rd element." << endl;
advance(iList,2);
cout << "The element is " << *iList << endl;
dTheDiff = distance( List.begin(), iList);
}
Output
The list is: A1 B2 C3 D4 E5 F6 G7
Advance to the 3rd element.
The element is C3
Requirements
Header: <iterator>