Материал из C\C++ эксперт
const_iterator
/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
#include <set>
int main()
{
// type of the collection
typedef std::set<int> IntSet;
IntSet coll; // set container for int values
/* insert elements from 1 to 6 in arbitrary order
* - value 1 gets inserted twice
*/
coll.insert(3);
coll.insert(1);
coll.insert(5);
coll.insert(4);
coll.insert(1);
coll.insert(6);
coll.insert(2);
/* print all elements
* - iterate over all elements
*/
IntSet::const_iterator pos;
for (pos = coll.begin(); pos != coll.end(); ++pos) {
std::cout << *pos << " ";
}
std::cout << std::endl;
}1 2 3 4 5 6
Display vector elements using const_iterator
#include <iostream>
using std::cout;
using std::endl;
#include <vector>
using std::vector;
template < typename T > void printVector( const vector< T > &integers2 );
int main()
{
int array[ 6 ] = { 1, 2, 3, 4, 5, 6 }; // initialize array
vector< int > integers; // create vector of ints
integers.push_back( 2 );
integers.push_back( 3 );
integers.push_back( 4 );
printVector( integers );
cout << endl;
return 0;
}
template < typename T > void printVector( const vector< T > &integers2 ){
typename vector< T >::const_iterator constIterator;
for ( constIterator = integers2.begin();
constIterator != integers2.end(); ++constIterator )
cout << *constIterator << " ";
}2 3 4
Use const_interator to loop through the set
#include <iostream>
#include <set>
#include <string>
using namespace std;
int main( ) {
set<string> setStr;
string s = "B";
setStr.insert(s);
s = "S";
setStr.insert(s);
s = "R";
setStr.insert(s);
s = "H";
setStr.insert(s);
for (set<string>::const_iterator p = setStr.begin( );p != setStr.end( ); ++p)
cout << *p << endl;
}B
H
R
S
