Eb

Engineer bro!

Sat Nov 13 2021 (2 years ago)

Engineer by mistake!

I am a software engineer by passion

In this article, we'll see that how can we use `count()`

and `count_if()`

function to count the element in the array.

The `count()`

function returns the number of elements in the range $$[first,last)[first,\; last)$$ satisfying specific criteria.

```
int main() {
vector<int> v{2, 2, 4, 8};
cout << count(v.begin(), v.end(), 2);
return 0;
}
```

**O/P**

2

count_if function returns the number of element for which predicates p returned true for the range $$[first,last)[first,\; last)$$.

Count the number of elements which are divisible by 2

```
int main() {
vector<int> v{2, 2, 4, 8};
cout << count_if(v.begin(), v.end(), [](int a) { return a % 2 == 0; });
return 0;
}
```

**O/P**

4

C

C++© 2021 dsabyte. All rights reserved