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#include <iostream>
#include <vector>
#include <algorithm>

using std::cout;
using std::endl;
using std::find;
using std::vector;

#define PRINT(X) cout << (#X) << " = " << X << endl

int main() {
        vector<int> v { 11, 22, 33, 44, 55, 66 };
        // `result` is an "iterator" which is sort of like a pointer.
        // v.begin() and v.end() return iterators too.
        auto result = find(v.begin(), v.end(), 33);

        // You can calculate the index from an iterator
        int index = result - v.begin();
        PRINT(index);

        // You can also do more.
        // `result + 1` gives you an iterator pointed to the next element
        // We then derefence the iterator to get its pointed-to value.
        PRINT( *(result + 1) );

        // This does what you'd expect.
        PRINT( *(result - 1) );

        return 0;
}