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vector::back

Returns a reference to the last element of the vector.

reference back( ); 
const_reference back( ) const;

Return Value

The last element of the vector. If the vector is empty, the return value is undefined.

Remarks

If the return value of back is assigned to a const_reference, the vector object cannot be modified. If the return value of back is assigned to a reference, the vector object can be modified.

When compiling with _SECURE_SCL 1, a runtime error will occur if you attempt to access an element in an empty vector. See Checked Iterators for more information.

Example

// vector_back.cpp
// compile with: /EHsc
#include <vector>
#include <iostream>

int main() {
   using namespace std;   
   vector <int> v1;
   
   v1.push_back( 10 );
   v1.push_back( 11 );

   int& i = v1.back( );
   const int& ii = v1.front( );

   cout << "The last integer of v1 is " << i << endl;
   i--;
   cout << "The next-to-last integer of v1 is "<< ii << endl;
}

Output

The last integer of v1 is 11
The next-to-last integer of v1 is 10

Requirements

Header: <vector>

Namespace: std

See Also

Reference

vector Class

vector::front and vector::back

Standard Template Library

Other Resources

vector Members