Python C++使用prefix sum mod k + hash map解Leetcode523 Continuous Subarray Sum

Python C++使用prefix sum mod k + hash map解Leetcode523 Continuous Subarray Sum
模k，前綴和 (mod k) 總共有 k 個可能，為 0,1,...k-1。
對於這個條件 1 less eq nums.length less eq 10^5 O(n^2) 解可能會導致 TLE。
對於此條件 1 less leq k less eq 2^31 - 1，陣列版本解決方案可能會導致 MLE。

然而，注意使用前綴和 mod k 的hash映射是一個有效解法。
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modulo k there are 0,1,...k-1 totally k possible for prefix sum (mod k).
For this constraint 1 less eq nums.length less eq 10^5 an O(n^2) solution may lead to TLE.
For this constraint 1 less leq k less eq 2^31 - 1, an array version solution might lead to MLE.

A hash map with care on prefix sum mod k to use is however a tip.
[codes on Leetcode]https://leetcode.com/problems/continuous-subarray-sum/solutions/5277106/mod-k-prefix-sum-hash-table-array-from-mle-to-86ms-beats-99-75/
[Leetcode Playlist]https://www.youtube.com/watch?v=B1GQlUN08lk&list=PLYRlUBnWnd5IdDHk2BjqXwesydU17z_xk