All problems

Range Sum Queries

Easy · prefix sum

You are given a list of integers nums and a list of queries. Each query is a pair [left, right] that names a stretch of nums from index left to index right, both ends included.

For every query, work out the total of the numbers in that stretch. Return a list with one total per query, in the same order as the queries. The list nums never changes between queries.

Examples

Example 1

Input: nums = [3, -2, 5, 1, 4], queries = [[0, 2], [1, 3], [4, 4]]

Output: [6, 4, 4]

3 + (-2) + 5 = 6, then (-2) + 5 + 1 = 4, and the last query is the single number 4.

Example 2

Input: nums = [10, 20, 30], queries = [[0, 2], [0, 0]]

Output: [60, 10]

Example 3

Input: nums = [-1, -1, -1, -1], queries = [[1, 2], [0, 3]]

Output: [-2, -4]

Constraints