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Author: MishkatIT

2058-find-the-minimum-and-maximum-number-of-nodes-between-critical-points/2058-find-the-minimum-and-maximum-number-of-nodes-between-critical-points.cpp

@@ -0,0 +1,42 @@
+/**
+ * Definition for singly-linked list.
+ * 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:
+    vector<int> nodesBetweenCriticalPoints(ListNode* head) {
+        ListNode* prv = nullptr;
+        ListNode* cur = head;
+        ListNode* nxt = head->next;
+        vector<int> cPoints;
+        int pos = 0;
+        while (nxt) {
+            if (prv && nxt) {
+                if (prv->val < cur->val && cur->val > nxt->val) {
+                    cPoints.push_back(pos);
+                }
+                if (prv->val > cur->val && cur->val < nxt->val) {
+                    cPoints.push_back(pos);
+                }
+            }
+            prv = cur;
+            cur = nxt;
+            nxt = nxt->next;
+            pos++;
+        }
+        vector<int> ans{-1, -1};
+        if (cPoints.size() < 2) return ans;
+        ans[0] = 1e9;
+        for (int i = 0; i + 1 < cPoints.size(); i++) {
+            ans[0] = min(ans[0], cPoints[i + 1] - cPoints[i]);
+        }
+        ans[1] = cPoints.back() - cPoints.front();
+        return ans;
+    }
+};