vector::operator[]
Returns a reference to the vector element at a specified position.
reference operator[]( size_type _Pos ); const_reference operator[]( size_type _Pos ) const;
Parameter
- _Pos
- The position of the vector element.
Return Value
If the position specified is greater than the size of the container, the result is undefined.
Remarks
If the return value of operator[] is assigned to a const_reference, the vector object cannot be modified. If the return value of operator[] is assigned to a reference, the vector object can be modified.
Example
// vector_op_ref.cpp
// compile with: /EHsc
#include <vector>
#include <iostream>
int main( )
{
using namespace std;
vector <int> v1;
v1.push_back( 10 );
v1.push_back( 20 );
int& i = v1[1];
cout << "The second integer of v1 is " << i << endl;
}
Output
The second integer of v1 is 20