Description
You are given an integer array nums of length n and a 2D integer array queries of size q, where queries[i] = [li, ri, ki, vi].
For each query, you must apply the following operations in order:
- Set
idx = li. - While
idx <= ri:- Update:
nums[idx] = (nums[idx] * vi) % (109 + 7) - Set
idx += ki.
- Update:
Return the bitwise XOR of all elements in nums after processing all queries.
Example 1:
Input: nums = [1,1,1], queries = [[0,2,1,4]]
Output: 4
Explanation:
- A single query
[0, 2, 1, 4]multiplies every element from index 0 through index 2 by 4. - The array changes from
[1, 1, 1]to[4, 4, 4]. - The XOR of all elements is
4 ^ 4 ^ 4 = 4.
Example 2:
Input: nums = [2,3,1,5,4], queries = [[1,4,2,3],[0,2,1,2]]
Output: 31
Explanation:
- The first query
[1, 4, 2, 3]multiplies the elements at indices 1 and 3 by 3, transforming the array to[2, 9, 1, 15, 4]. - The second query
[0, 2, 1, 2]multiplies the elements at indices 0, 1, and 2 by 2, resulting in[4, 18, 2, 15, 4]. - Finally, the XOR of all elements is
4 ^ 18 ^ 2 ^ 15 ^ 4 = 31.
Constraints:
1 <= n == nums.length <= 1031 <= nums[i] <= 1091 <= q == queries.length <= 103queries[i] = [li, ri, ki, vi]0 <= li <= ri < n1 <= ki <= n1 <= vi <= 105
Solutions
This function processes an array of numbers through a series of queries, where each query specifies a range (l to r), a step size (k), and a multiplier (v). For each query, the function iterates through elements at indices l, l + k, l + 2k, etc., up to index r, multiplying each element by v and keeping the result within bounds using modulo 10^9 + 7. After all queries have been applied, the function returns the XOR of all elements in the modified array (computed using reduce to combine all values with the ^ operator).
/**
* @param {number[]} nums
* @param {number[][]} queries
* @return {number}
*/
var xorAfterQueries = function(nums, queries) {
const mod = 10 ** 9 + 7;
for (const [l, r, k, v] of queries) {
let idx = l;
while (idx <= r) {
nums[idx] = (nums[idx] * v) % mod;
idx += k;
}
}
return nums.reduce((acc, el) => acc ^ el, 0);
};