Today I have done leetcode's March LeetCoding Challenge with cpp.

March LeetCoding Challenge 31

Description

Count Subarrays With Fixed Bounds

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 long countSubarrays(vector<int>& nums, int minK, int maxK) {
		long long answer = 0;
		int badIndex = -1;
		int minIndex = -1;
		int maxIndex = -1;
		for(int i = 0; i < nums.size(); ++i) {
			if(minK > nums[i] || nums[i] > maxK) {
				badIndex = i;
			}
			if(nums[i] == minK) {
				minIndex = i;
			}
			if(nums[i] == maxK) {
				maxIndex = i;
			}
			answer += max(0, min(minIndex, maxIndex) - badIndex);
		}

		return answer;  
	}
};