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1 files changed, 89 insertions, 0 deletions
-rw-r--r--Additional/Additional-2024-IS/solutions/remove-nodes-stack.cpp89
diff --git a/Additional/Additional-2024-IS/solutions/remove-nodes-stack.cpp b/Additional/Additional-2024-IS/solutions/remove-nodes-stack.cpp
new file mode 100644
index 0000000..a43dcfc
--- /dev/null
+++ b/Additional/Additional-2024-IS/solutions/remove-nodes-stack.cpp
@@ -0,0 +1,89 @@
+#include <climits>
+#include <iostream>
+#include <stack>
+
+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* removeNodes(ListNode* node)
+ {
+ if (!node || !node->next)
+ return node;
+
+ std::stack<ListNode*> listNodes;
+ int maxValue = INT_MIN;
+
+ ListNode* iter = nullptr;
+
+ while (node)
+ {
+ listNodes.push(node);
+ node = node->next;
+ }
+
+ while (!listNodes.empty())
+ {
+ ListNode* currentNode = listNodes.top();
+ listNodes.pop();
+
+ if (currentNode->val >= maxValue)
+ {
+ maxValue = currentNode->val;
+ currentNode->next = iter;
+ iter = currentNode;
+ }
+ else
+ {
+ delete currentNode;
+ }
+ }
+
+ return iter;
+ }
+};
+
+void freeList(ListNode* node)
+{
+ while (node)
+ {
+ ListNode* temp = node;
+ node = node->next;
+ delete temp;
+ }
+}
+
+int main()
+{
+ Solution s;
+
+ ListNode* result =
+ s.removeNodes(new ListNode(5, new ListNode(2, new ListNode(13, new ListNode(3, new ListNode(8))))));
+
+ ListNode* toDelete = result;
+
+ while (result)
+ {
+ std::cout << result->val << " ";
+ result = result->next;
+ }
+
+ freeList(toDelete);
+}