1627. Graph Connectivity With Threshold

https://leetcode.com/problems/graph-connectivity-with-threshold

Description

We have n cities labeled from 1 to n. Two different cities with labels x and y are directly connected by a bidirectional road if and only if x and y share a common divisor strictly greater than some threshold. More formally, cities with labels x and y have a road between them if there exists an integer z such that all of the following are true:

• x % z == 0,

• y % z == 0, and

• z > threshold.

Given the two integers, n and threshold, and an array of queries, you must determine for each queries[i] = [ai, bi] if cities ai and bi are connected directly or indirectly. (i.e. there is some path between them).

Return an array answer, where answer.length == queries.length and answer[i] is true if for the ith query, there is a path between ai and bi, or answer[i] is false if there is no path.

Example 1:

**Input:** n = 6, threshold = 2, queries = [[1,4],[2,5],[3,6]]
**Output:** [false,false,true]
**Explanation:** The divisors for each number:
1:   1
2:   1, 2
3:   1, 3
4:   1, 2, 4
5:   1, 5
6:   1, 2, 3, 6
Using the underlined divisors above the threshold, only cities 3 and 6 share a common divisor, so they are the
only ones directly connected. The result of each query:
[1,4]   1 is not connected to 4
[2,5]   2 is not connected to 5
[3,6]   3 is connected to 6 through path 3--6

Example 2:

**Input:** n = 6, threshold = 0, queries = [[4,5],[3,4],[3,2],[2,6],[1,3]]
**Output:** [true,true,true,true,true]
**Explanation:** The divisors for each number are the same as the previous example. However, since the threshold is 0,
all divisors can be used. Since all numbers share 1 as a divisor, all cities are connected.

Example 3:

**Input:** n = 5, threshold = 1, queries = [[4,5],[4,5],[3,2],[2,3],[3,4]]
**Output:** [false,false,false,false,false]
**Explanation:** Only cities 2 and 4 share a common divisor 2 which is strictly greater than the threshold 1, so they are the only ones directly connected.
Please notice that there can be multiple queries for the same pair of nodes [x, y], and that the query [x, y] is equivalent to the query [y, x].

Constraints:

• 2 <= n <= 104

• 0 <= threshold <= n

• 1 <= queries.length <= 105

• queries[i].length == 2

• 1 <= ai, bi <= cities

• ai != bi

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