811 - Subdomain Visit Count.

Medium

A website domain "discuss.leetcode.com" consists of various subdomains. At the top level, we have "com", at the next level, we have "leetcode.com" and at the lowest level, "discuss.leetcode.com". When we visit a domain like "discuss.leetcode.com", we will also visit the parent domains "leetcode.com" and "com" implicitly.

A count-paired domain is a domain that has one of the two formats "rep d1.d2.d3" or "rep d1.d2" where rep is the number of visits to the domain and d1.d2.d3 is the domain itself.

• For example, "9001 discuss.leetcode.com" is a count-paired domain that indicates that discuss.leetcode.com was visited 9001 times.

Given an array of count-paired domains cpdomains, return an array of the count-paired domains of each subdomain in the input. You may return the answer in any order.

Example 1:

Input: cpdomains = "9001 discuss.leetcode.com"

Output: "9001 leetcode.com","9001 discuss.leetcode.com","9001 com"

Explanation: We only have one website domain: "discuss.leetcode.com". As discussed above, the subdomain "leetcode.com" and "com" will also be visited. So they will all be visited 9001 times.

Example 2:

Input: cpdomains = "900 google.mail.com", "50 yahoo.com", "1 intel.mail.com", "5 wiki.org"

Output: "901 mail.com","50 yahoo.com","900 google.mail.com","5 wiki.org","5 org","1 intel.mail.com","951 com"

Explanation: We will visit "google.mail.com" 900 times, "yahoo.com" 50 times, "intel.mail.com" once and "wiki.org" 5 times. For the subdomains, we will visit "mail.com" 900 + 1 = 901 times, "com" 900 + 50 + 1 = 951 times, and "org" 5 times.

Constraints:

• 1 <= cpdomain.length <= 100

• 1 <= cpdomain[i].length <= 100

• cpdomain[i] follows either the <code>"rep_i d1_i.d2_i.d3_i"</code> format or the <code>"rep_i d1_i.d2_i"</code> format.

• <code>rep_i</code> is an integer in the range <code>1, 10⁴</code>.

• <code>d1_i</code>, <code>d2_i</code>, and <code>d3_i</code> consist of lowercase English letters.