NumArray (leetcode-in-java 1.21 API)

java.lang.Object
- g0301_0400.s0303_range_sum_query_immutable.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 Summary
  
  Constructors
  Constructor Description
  
  NumArray(int[] nums)
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  int sumRange(int i, int j)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- NumArray
```
public NumArray(int[] nums)
```

Method Detail

sumRange

public int sumRange(int i,
                    int j)