2527. Count Subarrays With Fixed Bounds¶

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2527. Count Subarrays With Fixed Bounds

Hard

You are given an integer array nums and two integers minK and maxK.

A fixed-bound subarray of nums is a subarray that satisfies the following conditions:

• The minimum value in the subarray is equal to minK.
• The maximum value in the subarray is equal to maxK.

Return the number of fixed-bound subarrays.

A subarray is a contiguous part of an array.

Example 1:

Input: nums = [1,3,5,2,7,5], minK = 1, maxK = 5
Output: 2
Explanation: The fixed-bound subarrays are [1,3,5] and [1,3,5,2].

Example 2:

Input: nums = [1,1,1,1], minK = 1, maxK = 1
Output: 10
Explanation: Every subarray of nums is a fixed-bound subarray. There are 10 possible subarrays.

Constraints:

• 2 <= nums.length <= 105
• 1 <= nums[i], minK, maxK <= 106

Solution¶

class Solution {
    public long countSubarrays(int[] nums, int minK, int maxK) {
        long res = 0;
        boolean minFound = false, maxFound = false;
        int start = 0, minStart = 0, maxStart = 0;
        for (int i = 0; i < nums.length; i++) {
            int num = nums[i];
            if (num < minK || num > maxK) {
                minFound = false;
                maxFound = false;
                start = i+1;
            }
            if (num == minK) {
                minFound = true;
                minStart = i;
            }
            if (num == maxK) {
                maxFound = true;
                maxStart = i;
            }
            if (minFound && maxFound) {
                res += (Math.min(minStart, maxStart) - start + 1);
            }
        }
        return res;
    }
}

Complexity Analysis¶

• Time Complexity: O(?)
• Space Complexity: O(?)

Approach¶

Detailed explanation of the approach will be added here