1using System;
2using System.Collections.Generic;
3
4class Solution {
5    public static IList<string> SubdomainVisits(string[] cpdomains) {
6        Dictionary<string, int> counts = new Dictionary<string, int>();
7        foreach (string cpdomain in cpdomains) {
8            string[] parts = cpdomain.Split(' ');
9            int count = int.Parse(parts[0]);
10            string domain = parts[1];
11
12            while (true) {
13                if (counts.ContainsKey(domain)) {
14                    counts[domain] += count;
15                } else {
16                    counts[domain] = count;
17                }
18
19                int dotIndex = domain.IndexOf('.');
20                if (dotIndex < 0) break;
21                domain = domain.Substring(dotIndex + 1);
22            }
23        }
24
25        List<string> result = new List<string>();
26        foreach (KeyValuePair<string, int> entry in counts) {
27            result.Add(entry.Value + " " + entry.Key);
28        }
29        return result;
30    }
31
32    public static void Main(string[] args) {
33        string[] cpdomains = {"9001 discuss.leetcode.com", "900 google.mail.com", "50 yahoo.com", "1 intel.mail.com", "5 wiki.org"};
34        IList<string> result = SubdomainVisits(cpdomains);
35        foreach (string res in result) {
36            Console.WriteLine(res);
37        }
38    }
39}

1#include <iostream>
#include <map>
#include <vector>
#include <sstream>
using namespace std;

struct TrieNode {
    map<string, TrieNode*> children;
    int count = 0;
};

void insert(TrieNode* root, vector<string>& tokens, int count) {
    TrieNode* node = root;
    for (auto it = tokens.rbegin(); it != tokens.rend(); ++it) {
        if (!node->children[*it])
            node->children[*it] = new TrieNode();
        node = node->children[*it];
        node->count += count;
    }
}

void dfs(TrieNode* node, string current, vector<string>& result) {
    if (node->count > 0) {
        result.push_back(to_string(node->count) + " " + current);
    }
    for (auto& child : node->children) {
        dfs(child.second, child.first + (current.empty() ? "" : ".") + current, result);
    }
}

vector<string> subdomainVisits(vector<string>& cpdomains) {
    TrieNode* root = new TrieNode();
    for (auto& domain : cpdomains) {
        stringstream ss(domain);
        int count;
        ss >> count;
        string dom;
        ss >> dom;
        vector<string> tokens;
        stringstream ss_tokens(dom);
        string token;
        while (getline(ss_tokens, token, '.')) {
            tokens.push_back(token);
        }
        insert(root, tokens, count);
    }
    vector<string> result;
    dfs(root, "", result);
    return result;
}

int main() {
    vector<string> cpdomains = {"9001 discuss.leetcode.com", "900 google.mail.com", "50 yahoo.com", "1 intel.mail.com", "5 wiki.org"};
    vector<string> result = subdomainVisits(cpdomains);
    for (string& s : result) {
        cout << s << endl;
    }
    return 0;
}