# set count() function in C++ STL

• Difficulty Level : Easy
• Last Updated : 08 Jun, 2021

The set::count() is a built-in function in C++ STL which returns the number of times an element occurs in the set. It can only return 1 or 0 as the set container contains unique elements only.
Syntax:

`set_name.count(element) `

Parameters: The function accepts one mandatory parameter element which specifies the element whose count is to be returned.
Return Value: The function returns 1 or 0 as the set contains unique elements only. It returns 1 if the value is present in the set container. It returns 0 if it is not present in the container.

Time Complexity : Time Complexity for count function is O(log N) where N is the number of elements present in the set

Difference between count and find function in a set is count returns 0 or 1 depending upon whether element is not present or present respectively whereas find function returns a iterator pointing to the value if present else next to the last value in the set.
Below is the illustration of the above function.

## CPP

 `// CPP program to demonstrate the``// set::count() function``#include ``using` `namespace` `std;``int` `main()``{` `    ``int` `arr[] = { 14, 12, 15, 11, 10 };` `    ``// initializes the set from an array``    ``set<``int``> s(arr, arr + 5);` `    ``// check if 11 is present or not``    ``if` `(s.count(11))``        ``cout << ``"11 is present in the set\n"``;``    ``else``        ``cout << ``"11 is not present in the set\n"``;` `    ``// checks if 18 is present or not``    ``if` `(s.count(18))``        ``cout << ``"18 is present in the set\n"``;``    ``else``        ``cout << ``"18 is not present in the set\n"``;` `    ``return` `0;``}`
Output:
```11 is present in the set
18 is not present in the set```

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