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unordered_map find() Function in C++ with Examples

C++ unordered_map find() Function: Here, we will learn about the find() function, its usages, syntax and examples.
Submitted by Shivang Yadav, on July 20, 2022

unordered_map:

An unordered_map is a special type of container that stores data in the form of key-value pairs in an unordered manner. The key stored is used to identify the data value mapped to it uniquely.

std::unordered_map::find() Function

The find() function is used to check for the presence of the pair with the given key value in the unordered_map.

std::unordered_map::find() Function Syntax:

unordered_mapName.find(k);
// k is the key value to be found

Parameter(s): It accepts a single parameter which is the key to be searched for.

Return Value: It returns an iterator that points to the element's key value if it is found otherwise it returns the end of the map iterator.

Examples:

CASE 1:
Input: unordered_map = {{1, a}, {2, e}, {10, a}}
key = 2
Output: key-value present.

CASE 2:
Input: unordered_map ={{1, a}, {2, e}, {10, a}}
key = 5
Output: key-value not present.

C++ unordered_map find() Function Example

#include <iostream>
#include <unordered_map>
using namespace std;

int main()
{
    unordered_map<int, char> myUnorderedMap = { { 1, 'a' }, { 5, 'x' }, { 9, 's' } };

    cout << "The elements of unordered_map are ";
    for (auto x : myUnorderedMap)
        cout << x.first << " : " << x.second << "\t";
    cout << endl;

    int k = 9;
    cout << "The element " << k << " is ";
    (myUnorderedMap.find(k) == myUnorderedMap.end()) ? cout << "Not Present\n" : cout << "Present\n";

    k = 67;
    cout << "The element " << k << " is ";
    (myUnorderedMap.find(k) == myUnorderedMap.end()) ? cout << "Not Present\n" : cout << "Present\n";

    return 0;
}

Output:

The elements of unordered_map are 9 : s 5 : x   1 : a
The element 9 is Present
The element 67 is Not Present

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