LeetCode-in-Java

2695. Array Wrapper

Easy

Create a class ArrayWrapper that accepts an array of integers in its constructor. This class should have two features:

• When two instances of this class are added together with the + operator, the resulting value is the sum of all the elements in both arrays.
• When the String() function is called on the instance, it will return a comma separated string surrounded by brackets. For example, [1,2,3].

Example 1:

Input: nums = [[1,2],[3,4]], operation = “Add”

Output: 10

Explanation:

const obj1 = new ArrayWrapper([1,2]); 
const obj2 = new ArrayWrapper([3,4]); 
obj1 + obj2; // 10

Example 2:

Input: nums = [[23,98,42,70]], operation = “String”

Output: “[23,98,42,70]”

Explanation:

const obj = new ArrayWrapper([23,98,42,70]); 
String(obj); // "[23,98,42,70]"

Example 3:

Input: nums = [[],[]], operation = “Add”

Output: 0

Explanation:

const obj1 = new ArrayWrapper([]); 
const obj2 = new ArrayWrapper([]); 
obj1 + obj2; // 0

Constraints:

• 0 <= nums.length <= 1000
• 0 <= nums[i] <= 1000
• Note: nums is the array passed to the constructor

Solution

class ArrayWrapper {
    nums: number[]
    constructor(nums: number[]) {
        this.nums = nums
    }

    valueOf() {
        return this.nums.reduce((n, a) => n + a, 0)
    }

    toString() {
        return '[' + this.nums.join(',') + ']'
    }
}

/*
 * const obj1 = new ArrayWrapper([1,2]);
 * const obj2 = new ArrayWrapper([3,4]);
 * obj1 + obj2; // 10
 * String(obj1); // "[1,2]"
 * String(obj2); // "[3,4]"
 */

export { ArrayWrapper }

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