811.子域名访问计数.md

811.子域名访问计数

/*
 * @lc app=leetcode.cn id=811 lang=typescript
 *
 * [811] 子域名访问计数
 */

// @lc code=start
function subdomainVisits(cpdomains: string[]): string[] {}
// @lc code=end

解法 1: 计数

function subdomainVisits(cpdomains: string[]): string[] {
  const res = new Map<string, number>()
  for (let str of cpdomains) {
    const strs = str.split(' ')
    const num = Number(strs[0]),
      names = strs[1].split('.')
    let s = ''
    for (let i = names.length - 1; i >= 0; i--) {
      if (i < names.length - 1) s = '.' + s
      s = names[i] + s
      res.set(s, (res.get(s) ?? 0) + num)
    }
  }
  return [...res].map(arr => `${arr[1]} ${arr[0]}`)
}

Case

test.each([
  {
    input: { cpdomains: ['9001 discuss.leetcode.com'] },
    output: ['9001 leetcode.com', '9001 discuss.leetcode.com', '9001 com'],
  },
  {
    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',
    ],
  },
])('input: cpdomains = $input.cpdomains', ({ input: { cpdomains }, output }) => {
  expect(subdomainVisits(cpdomains)).toIncludeSameMembers(output)
})