[C++] 백준 4195 친구 네트워크

#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <string>
 
using namespace std;
 
int parent[200001];
int friendcount[200001];
 
int FindParent(int now)
{
	if (now == parent[now])
		return now;
 
	else
		return parent[now] = FindParent(parent[now]);
}
 
void SetParent(int now, int set)
{
	int x = FindParent(now);
	int y = FindParent(set);
 
    if (x < y) 
    {
        parent[y] = x;
        friendcount[x] += friendcount[y];
    }
 
    else if (x > y) 
    {
        parent[x] = y;
        friendcount[y] += friendcount[x];
    }
}
 
using namespace std;
 
int arr[100001];
 
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(NULL);
 
    int n = 0;
    cin >> n;
 
    while (n--)
    {
        int F = 0;
        cin >> F;
 
        for (int i = 0; i < 200001; ++i)
        {
            parent[i] = i;
            friendcount[i] = 1;
        }
 
        int count = 0;
 
        unordered_map<string, int> unmap = {};
 
        for (int i = 0; i < F; ++i)
        {
            int friendnum1 = 0;
            int friendnum2 = 0;
            string s1, s2;
            cin >> s1 >> s2;
 
            if (unmap[s1])
            {
                friendnum1 = unmap[s1];
            }
 
            else 
            {
                unmap[s1] = ++count;
                friendnum1 = count;
            }
 
            if (unmap[s2])
            {
                friendnum2 = unmap[s2];
            }
 
            else 
            {
                unmap[s2] = ++count;
                friendnum2 = count;
            }
 
            SetParent(friendnum1, friendnum2);
 
            cout << friendcount[FindParent(friendnum1)] << '\n';
        }
    }
 
    return 0;
}

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