You are given an integer array nums of length n and a 2D array queries, where queries[i] = [li, ri]. For each queries[i]: Select a subset of indices within the range [li, ri] in nums. Decrement the values at the selected indices by 1. A Zero Array

isZeroArray.js

/**
 * @param {number[]} nums
 * @param {number[][]} queries
 * @return {boolean}
 */
var isZeroArray = function(nums, queries) {
    // Create a difference array initialized with zeros
    let diff = new Array(nums.length + 1).fill(0); 

    // Apply range updates using the difference array
    for (let [start, end] of queries) {
        diff[start] += 1;      // Increment at the start index
        diff[end + 1] -= 1;    // Decrement right after the end index
    }

    let cumulativeSum = 0; // Variable to track cumulative sum
    for (let i = 0; i < nums.length; i++) {
        cumulativeSum += diff[i]; // Update cumulative sum

        // If cumulativeSum is less than the corresponding nums value, return false
        if (cumulativeSum < nums[i]) return false; 
    }

    return true; // If all conditions are met, return true
};