iterator begin ();
const_iterator begin () const;
Return iterator to beginning
Returns an iterator referring to the first element in the vector container.
Notice that unlike member vector::front, which returns a reference to the first element, this function returns a random access iterator.
Parameters
none
Return Value
An iterator to the beginning of the sequence.
Both iterator and const_iterator are member types. In the vector class template, these are random access iterators.
Example
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
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// vector::begin
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
vector<int> myvector;
for (int i=1; i<=5; i++) myvector.push_back(i);
vector<int>::iterator it;
cout << "myvector contains:";
for ( it=myvector.begin() ; it < myvector.end(); it++ )
cout << " " << *it;
cout << endl;
return 0;
}
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Output:
myvector contains: 1 2 3 4 5
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Complexity
Constant.
See also
vector::end | Return iterator to end (public member function) |
vector::rbegin | Return reverse iterator to reverse beginning (public member function) |
vector::rend | Return reverse iterator to reverse end (public member function) |
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