@@ -32,20 +32,20 @@ numArray.sumRange(0, 5); // return (-2) + 0 + 3 + (-5) + 2 + (-1) = -3
3232```
3333
3434###Constraints
35- - ` 1 <= nums.length <=10000 `
36- - ` -100000 <= nums[i] <=100000 `
35+ - ` 1 <= nums.length <=10^4 `
36+ - ` -10^5 <= nums[i] <=10^5 `
3737- ` 0 <= left <= right < nums.length `
38- - At most` 10000 ` calls will be made to` sumRange ` .
38+ - At most` 10^4 ` calls will be made to` sumRange ` .
3939
4040##Intuition
4141###Solution 2
4242Directly returning the sum of the array elements can pass the tests, but if the test case is more stringent, it will fail.
4343So we still need to learn a more efficient solution.
4444
4545###Solution 1: Prefix Sum
46- * Use a new array` prefix_sums ` to save the sum of the previous elements.
47- * The first element of` prefix_sums ` is` 0 ` because the prefix sum** does not include the current element** .
48- * To find the` sum ` of the elements from index` left ` to` right ` (inclusive), just use` prefix_sums[right + 1] - prefix_sums[left] ` .
46+ - Use a new array` prefix_sums ` to save the sum of the previous elements.
47+ - The first element of` prefix_sums ` is` 0 ` because the prefix sum** does not include the current element** .
48+ - To find the` sum ` of the elements from index` left ` to` right ` (inclusive), just use` prefix_sums[right + 1] - prefix_sums[left] ` .
4949
5050##Complexity
5151* Time:` O(n) ` .