Leetcode Problem 2143. Choose Numbers From Two Arrays in Range

2143. Choose Numbers From Two Arrays in Range

Leetcode Solutions

Counting Dynamic Programming Approach

  1. Initialize a hashmap DP to store the number of ways to achieve a certain sum difference.
  2. Initialize a variable ans to store the final count of balanced ranges.
  3. Iterate through the elements of nums1 and nums2 using an index i.
  4. For each index i, create a new hashmap DP2 to store the updated number of ways for the current index.
  5. Update DP2 for the current index by considering the contribution of choosing nums1[i] and -nums2[i].
  6. For each sum difference key in the previous DP, update DP2 by adding the number of ways from DP to the corresponding sum differences after including nums1[i] or -nums2[i].
  7. Add the number of ways to achieve a sum difference of zero at the current index to ans.
  8. Set DP to DP2 for the next iteration.
  9. Return ans modulo 10^9 + 7.
UML Thumbnail

Top-down Dynamic Programming with Memoization

Ask Question

Programming Language
image/screenshot of info(optional)
Full Screen
Loading...

Suggested Answer

Answer
Full Screen
Copy Answer Code
Loading...