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/**
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* Value - type of the value stored in hashmap
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* N - number of buckets in hashmap
55
*/
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template
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class simple_kv {
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private:
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using key_type = pmem::obj::string;
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using bucket_type = pmem::obj::vector<
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std::pair>;
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using bucket_array_type = pmem::obj::array;
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using value_vector = pmem::obj::vector;
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bucket_array_type buckets;
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value_vector values;
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public:
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simple_kv() = default;
70
71
const Value &
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get(const std::string &key) const
73
{
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auto index = std::hash{}(key) % N;
75
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for (const auto &e : buckets[index]) {
77
if (e.first == key)
78
return values[e.second];
79
}
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throw std::out_of_range("no entry in simplekv");
82
}
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Chapter 11 Designing Data struCtures for persistent MeMory