#include <algorithm>
#include <iostream>
 
template <typename T>
std::vector<std::size_t> compute_ordered_indices(const std::vector<T>& v)
{
    std::vector<std::size_t> indices(v.size());
    std::iota(indices.begin(), indices.end(), 0u);
    std::sort(indices.begin(), indices.end(), [&](int lhs, int rhs) {
        return v[lhs] < v[rhs];
    });
    return indices;
}
 
int main() {
	std::vector<int> arr = {3, 2, 6, 4};
 
	auto indices = compute_ordered_indices(arr);
	for (auto index : indices) {
		std::cout << (1 + index) << " ";
	}
}

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