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// indirect_array example
#include <iostream> // std::cout
#include <cstddef> // std::size_t
#include <valarray> // std::valarray
int main ()
{
std::valarray<int> foo (8);
for (int i=0; i<8; ++i) foo[i]=i; // 0 1 2 3 4 5 6 7
std::size_t sel[] = {3,5,6};
std::valarray<std::size_t> selection (sel,3); // * * *
foo[selection] *= std::valarray<int>(10,3); // 0 1 2 30 4 50 60 7
foo[selection] = 0; // 0 1 2 0 4 0 0 7
std::cout << "foo:";
for (std::size_t i=0; i<foo.size(); ++i)
std::cout << ' ' << foo[i];
std::cout << '\n';
return 0;
}
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