[KOSSA] C++ Programming - 17th Study - STL #3
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The document provides code examples using C++ algorithms including find, find_if, remove, remove_if, sort, merge, and accumulate. It searches vectors for values, removes elements matching conditions, sorts elements, merges sorted vectors, and calculates sums, products and other accumulations of vector elements. Each example includes the algorithm call on vector iterators and checking the results.
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 { return n > 25; };
auto itFI = std::find_if(V.begin(), V.end(), GT25);
if (itFI != V.end())
std::cout << (*itFI) << std::endl;
}](https://image.slidesharecdn.com/kossacprogramming-17thstudy-stl3-150531132722-lva1-app6891/85/KOSSA-C-Programming-17th-Study-STL-3-10-320.jpg)
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 { return n % 2 == 1; };
auto itRI = std::remove_if(V.begin(), V.end(), isOdd);
if (itRI != V.end())
{
std::cout << "After remove_if() : " << V.size() << std::endl;
V.erase(itRI, V.end());
std::cout << "After erase() : " << V.size() << std::endl;
}
}](https://image.slidesharecdn.com/kossacprogramming-17thstudy-stl3-150531132722-lva1-app6891/85/KOSSA-C-Programming-17th-Study-STL-3-16-320.jpg)
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 { return a < b; };
std::merge(V.begin(), V.end(), V2.begin(), V2.end(), VR.begin(), isLess);
for (auto it = VR.begin(); it != VR.end(); it++)
std::cout << (*it) << 't';
std::cout << std::endl;
}](https://image.slidesharecdn.com/kossacprogramming-17thstudy-stl3-150531132722-lva1-app6891/85/KOSSA-C-Programming-17th-Study-STL-3-22-320.jpg)
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 { return a * b; };
int nMulti = std::accumulate(V.begin(), V.end(), 1, multi); // 인자의 곱
auto nSqure = [](int a, int b) { return a + b * b; };
int nSumSqure = std::accumulate(V.begin(), V.end(), 0, nSqure); // 제곱의 합
}](https://image.slidesharecdn.com/kossacprogramming-17thstudy-stl3-150531132722-lva1-app6891/85/KOSSA-C-Programming-17th-Study-STL-3-26-320.jpg)
[KOSSA] C++ Programming - 17th Study - STL #3
- 3. 3
- 4. 4
- 7. 7 template<class InputIterator, class Type> InputIterator find(InputIterator _First, InputIterator _Last, const Type& _Val);
- 8. 8 #include <iostream> #include <vector> #include <algorithm> void main() { std::vector<int> V{ 10, 20, 30, 40, 50 }; auto it30 = std::find(V.begin(), V.end(), 30); auto it25 = std::find(V.begin(), V.end(), 25); if (it30 != V.end()) std::cout << "Find 30 !" << std::endl; if (it25 != V.end()) std::cout << "Find 25 !" << std::endl; }
- 9. 9 template<class InputIterator, class Predicate> InputIterator find_if(InputIterator _First, InputIterator _Last, Predicate _Pred);
- 10. 10 #include <iostream> #include <vector> #include <algorithm> void main() { std::vector<int> V{ 10, 20, 30, 40, 50 }; auto GT25 = [](int n) { return n > 25; }; auto itFI = std::find_if(V.begin(), V.end(), GT25); if (itFI != V.end()) std::cout << (*itFI) << std::endl; }
- 13. 13 template<class InputIterator, class Type> InputIterator remove(InputIterator _First, InputIterator _Last, const Type& _Val);
- 14. 14 #include <iostream> #include <vector> #include <algorithm> void main() { std::vector<int> V{ 10, 20, 30, 40, 50 }; std::cout << "V.size() = " << V.size() << std::endl; auto itR = std::remove(V.begin(), V.end(), 40); if (itR != V.end()) { std::cout << "After remove() : " << V.size() << std::endl; V.erase(itR, V.end()); std::cout << "After erase() : " << V.size() << std::endl; } }
- 15. 15 template<class InputIterator, class Predicate> InputIterator remove_if(InputIterator _First, InputIterator _Last, Predicate _Pred);
- 16. 16 #include <iostream> #include <vector> #include <algorithm> void main() { std::vector<int> V{ 10, 15, 30, 45, 50 }; auto isOdd = [](int n) { return n % 2 == 1; }; auto itRI = std::remove_if(V.begin(), V.end(), isOdd); if (itRI != V.end()) { std::cout << "After remove_if() : " << V.size() << std::endl; V.erase(itRI, V.end()); std::cout << "After erase() : " << V.size() << std::endl; } }
- 19. 19 template<class RandomAccessIterator, class Pr> void sort(RandomAccessIterator _First, RandomAccessIterator _Last, BinaryPredicate _Comp);
- 20. 20 #include <iostream> #include <vector> #include <algorithm> #include <functional> void main() { std::vector<int> V{ 10, 30, 15, 50, 45 }; for (auto it = V.begin(); it != V.end(); it++) std::cout << (*it) << 't'; std::cout << std::endl; std::sort(V.begin(), V.end(), std::less<int>()); for (auto it = V.begin(); it != V.end(); it++) std::cout << (*it) << 't'; std::cout << std::endl; }
- 21. 21 template<class InputIterator1, class InputIterator2, class OutputIterator, class BinaryPredicate> OutputIterator merge(InputIterator1 _First1, InputIterator1 _Last1, InputIterator2 _First2, InputIterator2 _Last2, OutputIterator _Result, BinaryPredicate _Comp);
- 22. 22 #include <iostream> #include <vector> #include <deque> #include <algorithm> #include <functional> void main() { std::vector<int> V{ 10, 30, 15, 50, 45 }; std::sort(V.begin(), V.end(), std::less<int>()); std::deque<int> V2{ 13, 78, 57, 24, 69 }; std::sort(V2.begin(), V2.end(), std::less<int>()); std::vector<int> VR; VR.resize(V.size() + V2.size()); auto isLess = [](int a, int b) { return a < b; }; std::merge(V.begin(), V.end(), V2.begin(), V2.end(), VR.begin(), isLess); for (auto it = VR.begin(); it != VR.end(); it++) std::cout << (*it) << 't'; std::cout << std::endl; }
- 25. 25 template<class InputIterator, class Type, class BinaryOperation> Type accumulate(InputIterator _First, InputIterator _Last, Type _Val, BinaryOperation _Binary_op);
- 26. 26 #include <iostream> #include <vector> #include <numeric> void main() { std::vector<int> V{ 1, 2, 3, 4}; int nSum = std::accumulate(V.begin(), V.end(), 0); // vector의 합 int nSum10 = std::accumulate(V.begin(), V.end(), 10); // 10 + vector의 합 auto multi = [](int a, int b) { return a * b; }; int nMulti = std::accumulate(V.begin(), V.end(), 1, multi); // 인자의 곱 auto nSqure = [](int a, int b) { return a + b * b; }; int nSumSqure = std::accumulate(V.begin(), V.end(), 0, nSqure); // 제곱의 합 }