A type that provides the difference between two iterators that refer to elements within the same vector.
typedef typename Allocator::difference_type difference_type;
Remarks
A difference_type can also be described as the number of elements between two pointers.
An iterator is more commonly used to access a vector element.
Example
// vector_diff_type.cpp
// compile with: /EHsc
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main()
{
vector <int> vec;
vector <int>::iterator it_1, it_2;
// A vector with non-sequential values
vec.push_back(21);
vec.push_back(26);
vec.push_back(98);
vec.push_back(4);
vec.push_back(79);
vec.push_back(46);
vec.push_back(69);
// How far apart are 98 and 46 in the vector?
// (Making several assumptions for the sake of simplicity.)
it_1 = std::find(vec.begin(), vec.end(), 98);
it_2 = std::find(vec.begin(), vec.end(), 46);
vector <int>::difference_type distance = it_2 - it_1;
cout << "The value 46 occurs " << distance << " elements after the value 96." << endl;
}}
The value 46 occurs 3 elements after the value 96.
Requirements
Header: <vector>
Namespace: std