Problem: Range Sum Query - Immutable

15 min

Explore how to implement the Range Sum Query problem by designing a NumArray class that efficiently calculates the sum of elements between given indices in an integer array. Learn to handle multiple queries, understand constraints, and develop a custom data structure solution to optimize your approach to similar coding interview problems.

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 nums between indices i and j (inclusive), where i <= 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 nums between indices i and j (inclusive), i.e., the sum of nums[i] + nums[i + 1] + ... + nums[j].

Constraints:

$1 \leq$ nums.length $\leq 10^3$
$-10^5 \leq$ nums[i] $\leq 10^5$
$0 \leq$ i $\leq$ j $<$ nums.length
At most, $10^3$ calls will be made to sum_range.

Problem: Range Sum Query - Immutable

15 min

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 nums between indices i and j (inclusive), where i <= 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 nums between indices i and j (inclusive), i.e., the sum of nums[i] + nums[i + 1] + ... + nums[j].

Constraints:

$1 \leq$ nums.length $\leq 10^3$
$-10^5 \leq$ nums[i] $\leq 10^5$
$0 \leq$ i $\leq$ j $<$ nums.length
At most, $10^3$ calls will be made to sum_range.

Problem: Range Sum Query - Immutable

Statement

Examples

Understand the problem

Figure it out!

Try it yourself

Problem: Range Sum Query - Immutable

Statement

Examples

Understand the problem

Figure it out!

Try it yourself