C++ Unordered_set Library - find


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Description

It is used to searche for the container of an element with k as value and returns an iterator to it if found, otherwise it returns an iterator to unordered_set::end.

Declaration

Following is the declaration for std::unordered_set::find.

C++11

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

Parameters

k − K is the search element.

Return value

It returns an iterator to the element, if the specified value is found, or unordered_set::end if it is not found in the container.

Exceptions

Exception is thrown if any element comparison object throws exception.

Please note that invalid arguments cause undefined behavior.

Time complexity

constant time.

Example

The following example shows the usage of std::unordered_set::find.

#include <iostream>
#include <string>
#include <unordered_set>

int main () {
   std::unordered_set<std::string> myset = { "sai","ram,","krishna" };

   std::string input;
   std::cout << "Enter the myset char: ";
   getline (std::cin,input);

   std::unordered_set<std::string>::const_iterator got = myset.find (input);

   if ( got == myset.end() )
      std::cout << "not found in myset";
   else
      std::cout << *got << " is in myset";

   std::cout << std::endl;

   return 0;
}

Let us compile and run the above program, this will produce the following result −

Enter the myset char: krishna
krishna is in myset
unordered_set.htm
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