vector::vector
Constructs a vector of a specific size or with elements of a specific value or with a specific allocator or as a copy of all or part of some other vector.
vector( );
explicit vector(
const Allocator& _Al
);
explicit vector(
size_type _Count
);
vector(
size_type _Count,
const Type& _Val
);
vector(
size_type _Count,
const Type& _Val,
const Allocator& _Al
);
vector(
const vector& _Right
);
template<class InputIterator>
vector(
InputIterator _First,
InputIterator _Last
);
template<class InputIterator>
vector(
InputIterator _First,
InputIterator _Last,
const Allocator& _Al
);
vector(
vector&& _Right
);
Parameters
Parameter |
Description |
_Al |
The allocator class to use with this object. get_allocator returns the allocator class for the object. |
_Count |
The number of elements in the constructed vector. |
_Val |
The value of the elements in the constructed vector. |
_Right |
The vector of which the constructed vector is to be a copy. |
_First |
Position of the first element in the range of elements to be copied. |
_Last |
Position of the first element beyond the range of elements to be copied. |
Remarks
All constructors store an allocator object (_Al) and initialize the vector.
The first two constructors specify an empty initial vector. The second explicitly specifies the allocator type (_Al) to be used.
The third constructor specifies a repetition of a specified number (_Count) of elements of the default value for class Type.
The fourth and fifth constructors specify a repetition of (_Count) elements of value _Val.
The sixth constructor specifies a copy of the vector _Right.
The seventh and eighth constructors copy the range [_First, _Last) of a vector.
The last constructor moves the vector _Right.
Example
// vector_ctor.cpp
// compile with: /EHsc
#include <vector>
#include <iostream>
int main( )
{
using namespace std;
vector <int>::iterator v1_Iter, v2_Iter, v3_Iter, v4_Iter, v5_Iter, v6_Iter;
// Create an empty vector v0
vector <int> v0;
// Create a vector v1 with 3 elements of default value 0
vector <int> v1( 3 );
// Create a vector v2 with 5 elements of value 2
vector <int> v2( 5, 2);
// Create a vector v3 with 3 elements of value 1 and with the allocator
// of vector v2
vector <int> v3( 3, 1, v2.get_allocator( ) );
// Create a copy, vector v4, of vector v2
vector <int> v4( v2 );
// Create a new temporary vector for demonstrating copying ranges
vector <int> v5( 5 );
for ( int index = 0; index < 5; index++ )
v5[index] = index;
// Create a vector v6 by copying the range v5[_First, _Last)
vector <int> v6( v5.begin( ) + 1, v5.begin( ) + 3 );
cout << "v1 =" ;
for ( v1_Iter = v1.begin( ) ; v1_Iter != v1.end( ) ; v1_Iter++ )
cout << " " << *v1_Iter;
cout << endl;
cout << "v2 =" ;
for ( v2_Iter = v2.begin( ) ; v2_Iter != v2.end( ) ; v2_Iter++ )
cout << " " << *v2_Iter;
cout << endl;
cout << "v3 =" ;
for ( v3_Iter = v3.begin( ) ; v3_Iter != v3.end( ) ; v3_Iter++ )
cout << " " << *v3_Iter;
cout << endl;
cout << "v4 =" ;
for ( v4_Iter = v4.begin( ) ; v4_Iter != v4.end( ) ; v4_Iter++ )
cout << " " << *v4_Iter;
cout << endl;
cout << "v5 =";
for ( v5_Iter = v5.begin( ) ; v5_Iter != v5.end( ) ; v5_Iter++ )
cout << " " << *v5_Iter;
cout << endl;
cout << "v6 =";
for ( v6_Iter = v6.begin( ) ; v6_Iter != v6.end( ) ; v6_Iter++ )
cout << " " << *v6_Iter;
cout << endl;
// Move vector v2 to vector v7
vector <int> v7( move(v2) );
vector <int>::iterator v7_Iter;
cout << "v7 =" ;
for ( v7_Iter = v7.begin( ) ; v7_Iter != v7.end( ) ; v7_Iter++ )
cout << " " << *v7_Iter;
cout << endl;
}
v1 = 0 0 0 v2 = 2 2 2 2 2 v3 = 1 1 1 v4 = 2 2 2 2 2 v5 = 2 2 v6 = 1 2 v7 = 2 2 2 2 2
Requirements
Header: <vector>
Namespace: std
See Also
Reference
Other Resources
Change History
Date |
History |
Reason |
---|---|---|
December 2010 |
Updated sample to facilitate better understanding. |
Information enhancement. |