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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
    PRINT(result - v.begin());

    // 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.
    //
    // Expressions like `result - 1` and `result + 2` work as you expect too.
    PRINT( *(result + 1) );

    return 0;
}