What is the output and how?

#1

#include
#include
#include
using namespace std;
int main()
{
sets;
s.insert(1);
s.insert(5);
s.insert(7);
s.insert(2);
s.insert(12);
s.insert(10);
auto it = s.lower_bound(15);
cout<< *it <<endl;
return 0;
}

#2

@gopinathsah24
The lower_bound() method in C++ is used to return an iterator pointing to the first element in the range [first, last) which has a value not less than val. This means that the function returns the index of the next smallest number just greater than that number. since there is no element greater than 15 it just returns the index of last element + 1.