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Iterators

Method
MultimapContainer
Get constant iterators
const_iterator begin() const noexcept;
const_iterator end() const noexcept;
const_iterator cbegin() const noexcept;
const_iterator cend() const noexcept;
Get iterators
iterator begin() noexcept;
iterator end() noexcept;
Get reverse iterators
std::reverse_iterator<const_iterator> rbegin() const noexcept;
std::reverse_iterator<const_iterator> rend() const noexcept;
std::reverse_iterator<iterator> rbegin() noexcept;
std::reverse_iterator<iterator> rend() noexcept;
Get constant reverse iterators
std::reverse_iterator<const_iterator> crbegin() const noexcept;
std::reverse_iterator<const_iterator> crend() const noexcept;

Return value

  • begin() - Iterator to the first element in the container
  • end() - Iterator to the past-the-end element in the container (see notes)

Complexity

\[ O(1) \]

Notes

All requirements of a SpatialContainer also apply here.

Info

See the section on spatial containers / iterators for more information.

Example

Continuing from the previous example:

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std::cout << "Iterators:" << std::endl;
for (const auto& [point, value]: pf) {
    std::cout << point << " -> " << value << std::endl;
}

std::cout << "Reversed Iterators:" << std::endl;
for (auto it = pf.rbegin(); it != pf.rend(); ++it) {
    std::cout << it->first << " -> " << it->second << std::endl;
}

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print('Iterators')
for [point, value] in m:
    print(point, '->', value)

print('Reversed Iterators')
for [point, value] in reversed(m):
    print(point, '->', value)

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Iterators:
[-2.14255, -0.518684, -2.92346] -> 32
[-1.63295, 0.912108, -2.12953] -> 36
[-0.653036, 0.927688, -0.813932] -> 13
[-0.508188, 0.871096, -2.25287] -> 32
[0.453686, 1.02632, -2.24833] -> 30
[0.693712, 1.12267, -1.37375] -> 12
[-2.57664, -1.52034, 0.600798] -> 17
[-2.55905, -0.271349, 0.898137] -> 6
[-2.31613, -0.219302, 0] -> 8
[-0.894115, 1.01387, 0.462008] -> 11
[-2.3912, 0.395611, 2.78224] -> 11
[-0.639149, 1.89515, 0.858653] -> 10
[-0.401531, 2.30172, 0.58125] -> 39
[-1.09756, 1.33135, 0.569513] -> 20
[-1.45049, 1.35763, 0.606019] -> 17
[-0.00292544, 1.29632, -0.578346] -> 20
[0.0728106, 1.91877, 0.399664] -> 25
[0.152711, 1.99514, -0.112665] -> 13
[0.157424, 2.30954, -1.23614] -> 6
[1.49101, 3.24052, 0.724771] -> 24
Reversed Iterators:
[1.49101, 3.24052, 0.724771] -> 24
[0.157424, 2.30954, -1.23614] -> 6
[0.152711, 1.99514, -0.112665] -> 13
[0.0728106, 1.91877, 0.399664] -> 25
[-0.00292544, 1.29632, -0.578346] -> 20
[-1.45049, 1.35763, 0.606019] -> 17
[-1.09756, 1.33135, 0.569513] -> 20
[-0.401531, 2.30172, 0.58125] -> 39
[-0.639149, 1.89515, 0.858653] -> 10
[-2.3912, 0.395611, 2.78224] -> 11
[-0.894115, 1.01387, 0.462008] -> 11
[-2.31613, -0.219302, 0] -> 8
[-2.55905, -0.271349, 0.898137] -> 6
[-2.57664, -1.52034, 0.600798] -> 17
[0.693712, 1.12267, -1.37375] -> 12
[0.453686, 1.02632, -2.24833] -> 30
[-0.508188, 0.871096, -2.25287] -> 32
[-0.653036, 0.927688, -0.813932] -> 13
[-1.63295, 0.912108, -2.12953] -> 36
[-2.14255, -0.518684, -2.92346] -> 32