stl:vector:vector_operators

C++ Reference

Vector operators

Syntax:

    #include <vector>
    TYPE& operator[]( size_type index );
    const TYPE& operator[]( size_type index ) const;
    vector operator=(const vector& c2);
    bool operator==(const vector& c1, const vector& c2);
    bool operator!=(const vector& c1, const vector& c2);
    bool operator<(const vector& c1, const vector& c2);
    bool operator>(const vector& c1, const vector& c2);
    bool operator<=(const vector& c1, const vector& c2);
    bool operator>=(const vector& c1, const vector& c2);

All of the C++ containers can be compared and assigned with the standard comparison operators: ==, !=, <=, >=, <, >, and =. Individual elements of a vector can be examined with the [] operator.

Performing a comparison or assigning one vector to another takes linear time.

The [] operator runs in constant time.

Two vectors are equal if:

  1. Their size is the same, and
  2. Each member in location i in one vector is equal to the the member in location i in the other vector.

Comparisons among vectors are done lexicographically.

For example, the following code uses the [] operator to access all of the elements of a vector:

   vector<int> v( 5, 1 );
   for( int i = 0; i < v.size(); i++ ) {
     cout << "Element " << i << " is " << v[i] << endl;
   }

Related Topics: at