unordered_set find() function in C++ STL

The unordered_set::find() function is a built-in function in C++ STL which is used to search for an element in the container. It returns an iterator to the element, if found else, it returns an iterator pointing to unordered_set::end().

Syntax :

unordered_set_name.find(key)

Parameter: This function accepts a mandatory parameter key which specifies the element to be searched for.

Return Value: It returns an iterator to the element if found, else returns an iterator pointing to the end of unordered_set.

Below programs illustrate the unordered_set::find() function:

Program 1:

// C++ program to illustrate the 
// unordered_set::find() function 
  
#include <iostream> 
#include <string> 
#include <unordered_set> 
  
using namespace std; 
  
int main() 
{ 
  
    unordered_set<string> sampleSet = { "geeks1", "for", "geeks2" }; 
  
    // use of find() function 
    if (sampleSet.find("geeks1") != sampleSet.end()) { 
        cout << "element found." << endl; 
    } 
    else { 
        cout << "element not found" << endl; 
    } 
  
    return 0; 
} 

Output:

element found.

Program 2:

// CPP program to illustrate the 
// unordered_set::find() function 
  
#include <iostream> 
#include <string> 
#include <unordered_set> 
  
using namespace std; 
  
int main() 
{ 
  
    unordered_set<string> sampleSet = { "geeks1", "for", "geeks2" }; 
  
    // use of find() function 
    if (sampleSet.find("geeksforgeeks") != sampleSet.end()) { 
        cout << "found" << endl; 
    } 
    else { 
        cout << "Not found" << endl; 
    } 
  
    return 0; 
} 

Output:

Not found

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