Aryadev Chavali
36d5eb111a
Pretty simple, returns the last node as that's the new root node. Uses default parameters to make sure the first node has next set to null.
77 lines
1.3 KiB
C++
77 lines
1.3 KiB
C++
/* list.cpp
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* Date: 2021-11-20
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* Author: Aryadev Chavali
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*/
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#include <cstdio>
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#include <iostream>
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#include <cstdlib>
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template <typename T>
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struct List
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{
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T value;
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struct List<T> *next;
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~List()
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{
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if (next == NULL)
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return;
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delete next;
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}
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};
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template <typename T>
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List<T> *append(List<T> *lst, T value)
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{
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List<T> *node;
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if (lst == NULL)
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{
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node = new List<T>;
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node->value = value;
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node->next = NULL;
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return node;
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}
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for (node = lst; node->next != NULL; node = node->next)
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continue;
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node->next = new List<T>;
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node->next->value = value;
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node->next->next = NULL;
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return lst;
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}
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/** Reverse a list
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*/
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template <typename T>
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List<T> *reverse(List<T> *lst, List<T> *prev = NULL)
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{
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auto next = lst->next;
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lst->next = prev;
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if (next == NULL)
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return lst;
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return reverse(next, lst);
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}
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template <typename T>
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std::ostream& operator<<(std::ostream& ostream, const List<T> *lst)
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{
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if (!lst)
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return ostream;
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ostream << "|" << lst->value << lst->next;
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return ostream;
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}
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int main(void)
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{
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auto lst = append<int>(NULL, 1);
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for (int i = 2; i < 10; ++i)
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lst = append(lst, i);
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std::cout << lst << std::endl;
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lst = reverse(lst);
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std::cout << lst << std::endl;
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delete lst;
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return 0;
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}
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