Class NumArray


  • public class NumArray
    extends Object
    303 - Range Sum Query - Immutable\. Easy Given an integer array `nums`, handle multiple queries of the following type: 1. Calculate the **sum** of the elements of `nums` between indices `left` and `right` **inclusive** where `left <= right`. Implement the `NumArray` class: * `NumArray(int[] nums)` Initializes the object with the integer array `nums`. * `int sumRange(int left, int right)` Returns the **sum** of the elements of `nums` between indices `left` and `right` **inclusive** (i.e. `nums[left] + nums[left + 1] + ... + nums[right]`). **Example 1:** **Input** ["NumArray", "sumRange", "sumRange", "sumRange"] [[[-2, 0, 3, -5, 2, -1]], [0, 2], [2, 5], [0, 5]] **Output:** [null, 1, -1, -3] **Explanation:** NumArray numArray = new NumArray([-2, 0, 3, -5, 2, -1]); numArray.sumRange(0, 2); // return (-2) + 0 + 3 = 1 numArray.sumRange(2, 5); // return 3 + (-5) + 2 + (-1) = -1 numArray.sumRange(0, 5); // return (-2) + 0 + 3 + (-5) + 2 + (-1) = -3 **Constraints:** * 1 <= nums.length <= 104 * -105 <= nums[i] <= 105 * `0 <= left <= right < nums.length` * At most 104 calls will be made to `sumRange`.
    • Constructor Detail

      • NumArray

        public NumArray​(int[] nums)
    • Method Detail

      • sumRange

        public int sumRange​(int i,
                            int j)