Check out example codes for "get index of value c++". It will help you in understanding the concepts better.

Code Example 1

vector<int> arr = { 6, 3, 5, 2, 8 };
vector<int>::iterator itr = std::find(arr.begin(), arr.end(), elem);

if (itr != end(arr)) {
	cout << "Element " << elem << " is present at index " << distance(arr, itr) << " in the given array";
}
else {
	cout << "Element is not present in the given array";
}

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