, the pattern [1,0,-1] indicates that we are looking for a sequence where the first number is smaller than the second, the second is equal to the third, and the third is greater than the fourth. In the array nums, the subarrays [1,4,4,1], and [3,5,5,3] match this pattern. Hence, there are 2 subarrays in nums that match the pattern.

Constraints

2 <= n == nums.length <= 100
1 <= nums[i] <= 10^9
1 <= m == pattern.length < n
-1 <= pattern[i] <= 1

Solution

Method 1 – Sliding Window Pattern Matching

Intuition

The key idea is to check every subarray of length m+1 in nums and compare the difference pattern with the given pattern. If all differences match the pattern, we count it. This works because the constraints are small, so a brute-force sliding window is efficient.

Approach

Loop through all possible starting indices

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