Solution: Range Sum Query - Immutable
Explore how to efficiently solve the range sum query problem by implementing a NumArray class with a prefix sum array. Understand how to initialize and use the prefix sums to answer sum queries in constant time, improving performance for multiple queries.
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Statement
You are given an integer array, nums, and you need to handle multiple queries of the following type:
Query: Calculate the sum of elements in
numsbetween indicesiandj(inclusive), wherei <= j.
Implement the NumArray class to support the following operations efficiently:
Constructor: Initializes the object with the integer array
nums.sumRange(i, j): Returns the sum of the elements of
numsbetween indicesiandj(inclusive), i.e., the sum ofnums[i] + nums[i + 1] + ... + nums[j].
Constraints:
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