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map::empty

Tests if a map is empty.

bool empty( ) const;

Return Value

true if the map is empty; false if the map is nonempty.

Example

// map_empty.cpp
// compile with: /EHsc
#include <map>
#include <iostream>

int main( )
{
   using namespace std;
   map <int, int> m1, m2;

   typedef pair <int, int> Int_Pair;
   m1.insert ( Int_Pair ( 1, 1 ) );

   if ( m1.empty( ) )
      cout << "The map m1 is empty." << endl;
   else
      cout << "The map m1 is not empty." << endl;

   if ( m2.empty( ) )
      cout << "The map m2 is empty." << endl;
   else
      cout << "The map m2 is not empty." << endl;
}
The map m1 is not empty.
The map m2 is empty.

Requirements

Header: <map>

Namespace: std

See Also

Reference

map Class

Standard Template Library