#include <algorithm>
#include <vector>
vector<int> vec;
//can have other data types instead of int but must same datatype as item
std::find(vec.begin(), vec.end(), item) != vec.end()
auto it = find(vec.begin(),vec,end(), item)!
if(it != vec.end()){
int index = it - vec.begin();
}
it = find (vec.begin(), vec.end(), ser);
if (it != vec.end())
{
cout << "Element " << ser <<" found at position : " ;
cout << it - vec.begin() << " (counting from zero)
" ;
}
else{
cout << "Element not found.
";
}