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public member function

<map>

      iterator find (const key_type& k);const_iterator find (const key_type& k) const;

Get iterator to element

key equivalent to k and returns an iterator to it if found, otherwise it returns an iterator to

Two keys are considered equivalent if the container’s false reflexively (i.e., no matter the order in which the elements are passed as arguments).

Another member function,

Searches the container for an element with aequivalent toand returns an iterator to it if found, otherwise it returns an iterator to map::end Twoare considered equivalent if the container’s comparison object returnsreflexively (i.e., no matter the order in which the elements are passed as arguments).Another member function, map::count , can be used to just check whether a particular key exists.

Parameters

k
Key to be searched for.
Member type key_type is the type of the keys for the elements in the container, defined in map as an alias of its first template parameter (Key).

Return value

An iterator to the element, if an element with specified key is found, or

If the const_iterator. Otherwise, it returns an iterator.

Member types iterator and const_iterator are value_type).
Notice that value_type in pair<const key_type, mapped_type>.

An iterator to the element, if an element with specified key is found, or map::end otherwise.If the map object is const-qualified, the function returns a. Otherwise, it returns anMember typesandare bidirectional iterator types pointing to elements (of type).Notice thatin map containers is an alias of

Example

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// map::find
#include <iostream>
#include <map>

int main ()
{
  std::map<char,int> mymap;
  std::map<char,int>::iterator it;

  mymap['a']=50;
  mymap['b']=100;
  mymap['c']=150;
  mymap['d']=200;

  it = mymap.find('b');
  if (it != mymap.end())
    mymap.erase (it);

  // print content:
  std::cout << "elements in mymap:" << '\n';
  std::cout << "a => " << mymap.find('a')->second << '\n';
  std::cout << "c => " << mymap.find('c')->second << '\n';
  std::cout << "d => " << mymap.find('d')->second << '\n';

  return 0;
}

Output:

elements in mymap:
a => 50
c => 150
d => 200

Output:

Complexity

Logarithmic in

Logarithmic in size

Iterator validity

No changes.

Data races

The container is accessed (neither the const nor the non-const versions modify the container).
No mapped values are accessed: concurrently accessing or modifying elements is safe.

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the container.

See also

mtoplist