### 811 Subdomain Visit Count

```/**
*
* Ashish Patel
* e: ashishsushilPatel@gmail.com
* w: https://ashish.me
*
*/

/*
* A website domain like "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.
*
* Now, call a "count-paired domain" to be a count (representing the number of
* visits this domain received), followed by a space, followed by the address.
* An example of a count-paired domain might be "9001 discuss.leetcode.com".
*
* We are given a list cpdomains of count-paired domains. We would like a list
* of count-paired domains, (in the same format as the input, and in any order),
* that explicitly counts the number of visits to each subdomain.
*
* Example 1:
* Input:
* ["9001 discuss.leetcode.com"]
* Output:
* ["9001 discuss.leetcode.com", "9001 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.
*/

function subdomainVisitCount(domains) {
let cache = {}
let result = []
for (let i = 0; i < domains.length; i++) {
const count = Number(domains[i].split(' '))
const domain = domains[i].split(' ')
const subdomains = domain.split('.')
let subdomain = subdomains[subdomains.length - 1]
cache[subdomain] = (cache[subdomain] || 0) + count
for (let i = subdomains.length - 2; i >= 0; i--) {
subdomain = subdomains[i] + '.' + subdomain
cache[subdomain] = (cache[subdomain] || 0) + count
}
}

for (const key in cache) {
result.push(`\${cache[key]} \${key}`)
}
return result.sort()
}

test('subdomain Visit Count', () => {
expect(subdomainVisitCount(['9001 discuss.leetcode.com'])).toEqual([
'9001 discuss.leetcode.com',
'9001 leetcode.com',
'9001 com',
].sort())
})```

Created 2020-04-25T22:07:19+00:00 · Edit