LeetCode: 92. Reverse Linked List II;

- accepted;

leetcode/problems/reverse-linked-list-ii/compile-and-run.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+set -x
+
+clang++ main.cpp -W -Wall -std=c++17 -O2 -fsanitize=address && ./a.out

leetcode/problems/reverse-linked-list-ii/main.cpp

@@ -0,0 +1,90 @@
+/*
+92. Reverse Linked List II
+https://leetcode.com/problems/reverse-linked-list-ii
+*/
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+
+struct ListNode {
+    int val;
+    ListNode *next;
+    ListNode() : val(0), next(nullptr) {}
+    ListNode(int x) : val(x), next(nullptr) {}
+    ListNode(int x, ListNode *next) : val(x), next(next) {}
+};
+
+class Solution {
+public:
+    ListNode* reverseBetween(ListNode* head, int left, int right) {
+        ListNode *current = head;
+        ListNode *previous = nullptr;
+
+        while (left > 1) {
+            previous = current;
+            current = current->next;
+
+            left--;
+            right--;
+        }
+
+        cout << current->val << endl;
+
+        ListNode *currentBeforeInverting = current;
+        ListNode *previousBeforeInverting = previous;
+
+        while (right-- > 0) {
+            ListNode *next = current->next;
+
+            current->next = previous;
+            previous = current;
+            current = next;
+        }
+
+        currentBeforeInverting->next = current;
+
+        if (previousBeforeInverting == nullptr) {
+            head = previous;
+        }
+        else {
+            previousBeforeInverting->next = previous;
+        }
+
+        return head;
+    }
+};
+
+class RecursiveSolution {
+public:
+    ListNode* reverseBetween(ListNode* head, int left, int right) {
+        if (left > 1) {
+            head->next = reverseBetween(head->next, left - 1, right - 1);
+        }
+        else {
+            ListNode* curr = head;
+            ListNode* prev = nullptr;
+
+            while (right-- > 0) {
+                ListNode *next = curr->next;
+
+                curr->next = prev;
+                prev = curr;
+                curr = next;
+            }
+
+            head->next = curr;
+
+            return prev;
+        }
+
+        return head;
+    }
+};
+
+int main(void) {
+    ios::sync_with_stdio(false);
+
+    return EXIT_SUCCESS;
+}