C++ Tutorial/STL Algorithms Helper/distance

Материал из C\C++ эксперт
Перейти к: навигация, поиск

distance

#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
int main( ) {
  vector<int> v;
  v.push_back(0);
  v.push_back(1);
  v.push_back(2);
  cout << v.size( ) << endl;
  cout << distance(v.begin( ), v.end( )) << endl;
}
3
3

Get the distance between two element in a list

/* 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 <list>
#include <algorithm>
using namespace std;
int main()
{
    list<int> coll;
    // insert elements from -3 to 9
    for (int i=-3; i<=9; ++i) {
        coll.push_back(i);
    }
    // search element with value 5
    list<int>::iterator pos;
    pos = find (coll.begin(), coll.end(),    // range
                5);                          // value
    if (pos != coll.end()) {
        // process and print difference from the beginning
        cout << "difference between beginning and 5: "
             << distance(coll.begin(),pos) << endl;
    }
    else {
        cout << "5 not found" << endl;
    }
}
difference between beginning and 5: 8