64 lines
1.4 KiB
Markdown
64 lines
1.4 KiB
Markdown
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# Sort
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#### 2022-06-11
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___
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##### Algorithms:
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#algorithm #sort
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##### Difficulty:
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#CS_analysis #difficulty-easy
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##### Related problems:
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```expander
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tag:#coding_problem tag:#sort -tag:#template_remove_me
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```
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- [[Leetcode Intersection-of-Two-Arrays-II]]
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##### Links:
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- [cpp reference](https://en.cppreference.com/w/cpp/algorithm/sort)
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___
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### What is Sort?
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Sorts the elements in the range `[first, last)` in non-descending order. The order of equal elements is not guaranteed to be preserved.
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The default Compare function is less: `<`
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### Example
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```cpp
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#include <algorithm>
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#include <functional>
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#include <array>
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#include <iostream>
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#include <string_view>
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int main()
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{
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std::array<int, 10> s = {5, 7, 4, 2, 8, 6, 1, 9, 0, 3};
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auto print = [&s](std::string_view const rem) {
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for (auto a : s) {
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std::cout << a << ' ';
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}
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std::cout << ": " << rem << '\n';
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};
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std::sort(s.begin(), s.end());
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print("sorted with the default operator<");
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std::sort(s.begin(), s.end(), std::greater<int>());
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print("sorted with the standard library compare function object");
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struct {
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bool operator()(int a, int b) const { return a < b; }
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} customLess;
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std::sort(s.begin(), s.end(), customLess);
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print("sorted with a custom function object");
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std::sort(s.begin(), s.end(), [](int a, int b) {
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return a > b;
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});
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print("sorted with a lambda expression");
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}
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```
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