Solution: Next Greater Element I

Explore how to find the next greater element for elements in one array based on their position in another using hash maps and monotonic stacks. This lesson helps you understand an optimized approach with O(n) time complexity and walk through the implementation steps to solve this common coding interview pattern effectively.

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Statement
Solution
- Naive approach
- Optimized approach using hash map

Statement

Given the two distinct integer arrays, nums1 and nums2, where nums1 is a subset of nums2, find all the next greater elements for nums1 values in the corresponding places of nums2.

In general, the next greater element of an element, $x$ , in an array is the first greater element present on the right side of $x$ in the same array. However, in the context of this problem, for each element $x$ in nums1, find the next greater element present on the right side of $x$ in nums2 and store it in the ans array. If there is no such element, store ...