2058 - Find the Minimum and Maximum Number of Nodes Between Critical Points

 JAVA

class Solution {

    public int[] nodesBetweenCriticalPoints(ListNode head) {
        ListNode prev = head;
        ListNode curr = head.next;
        int first = 0, last = 0;
        int i = 1;
        int[] ans = new int[] {Integer.MAX_VALUE, Integer.MIN_VALUE};
        while (curr.next != null) {
            if (curr.val < Math.min(prev.val, curr.next.val)
                || curr.val > Math.max(prev.val, curr.next.val)) {
                if (last == 0) {
                    first = i;
                    last = i;
                } else {
                    ans[0] = Math.min(ans[0], i - last);
                    ans[1] = i - first;
                    last = i;
                }
            }
            ++i;
            prev = curr;
            curr = curr.next;
        }
        return first == last ? new int[] {-1, -1} : ans;
    }
}

C++

class Solution {
public:
    vector<int> nodesBetweenCriticalPoints(ListNode* head) {
        ListNode* prev = head;
        ListNode* curr = head->next;
        int first = 0, last = 0;
        int i = 1;
        vector<int> ans(2, INT_MAX);
        while (curr->next) {
            if (curr->val < min(prev->val, curr->next->val) || curr->val > max(prev->val, curr->next->val)) {
                if (last == 0)
                    first = i;
                else {
                    ans[0] = min(ans[0], i - last);
                    ans[1] = i - first;
                }
                last = i;
            }
            ++i;
            prev = curr;
            curr = curr->next;
        }
        if (first == last) return {-1, -1};
        return ans;
    }
};