C++ STL iterator, operator== program example
Compiler: Visual C++ Express Edition 2005
Compiled on Platform: Windows XP Pro SP2
Header file: Standard
Additional project setting: Set project to be compiled as C++
Project -> your_project_name Properties -> Configuration Properties -> C/C++ -> Advanced -> Compiled As: Compiled as C++ Code (/TP)
Other info: none
To do: Using the C++ iterator, operator== to test if the iterator object on the left side of the operator is equal to the iterator object on the right side in C++ programming
To show: How to use the C++ iterator, operator== to test if the iterator object on the left side of the operator is equal to the iterator object on the right side in C++ programming
// C++ STL iterator, operator==
#include <iterator>
#include <vector>
#include <iostream>
using namespace std;
int main(void)
{
int i;
// vector container
vector<int> vec;
// vector iterator
vector <int>::iterator veciter;
// insert/push data into vector
for(i = 11; i<15; ++i)
vec.push_back(i);
// print the data
cout<<"The vec vector data: ";
for(veciter = vec.begin(); veciter != vec.end(); veciter++)
cout<<*veciter<<" ";
cout<<endl;
// initializing reverse_iterators to the last element
vector<int>::reverse_iterator rvecpos1 = vec.rbegin(), rvecpos2 = vec.rbegin();
cout<<"\nThe iterators rvecpos1 and rvecpos2 points to the first element in the reversed sequence: "<<*rvecpos1<<endl;
cout<<"\nOperation: rvecpos1 == rvecpos2"<<endl;
if(rvecpos1 == rvecpos2)
cout<<"The iterators are equal."<<endl;
else
cout<<"The iterators are not equal."<<endl;
rvecpos1++;
cout<<"\nThe iterator rvecpos1 now points to the second element in the reversed sequence: "<<*rvecpos1<<endl;
cout<<"\nOperation: rvecpos1 == rvecpos2"<<endl;
if(rvecpos1 == rvecpos2)
cout<<"The iterators are equal."<<endl;
else
cout<<"The iterators are not equal."<<endl;
return 0;
}
Output examples:
The vec vector data: 11 12 13 14
The iterators rvecpos1 and rvecpos2 points to the first element in the reversed sequence: 14
Operation: rvecpos1 == rvecpos2
The iterators are equal.
The iterator rvecpos1 now points to the second element in the reversed sequence: 13
Operation: rvecpos1 == rvecpos2
The iterators are not equal.
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