CF EDU DSU: C: Experience

#include <bits/stdc++.h>
using namespace std;
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
#define NeedForSpeed                  \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL);                    \
    cout.tie(NULL);
#define int long long
#define all(x) (x).begin(), (x).end()
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vpi;
#define f first
#define s second
#define endl "\n"
const int mod = 1000000007;
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
struct DSU
{
    vector<int> parent, size, points, extra_points;
    DSU(int n) : parent(n), size(n, 1), points(n, 0), extra_points(n, 0)
    {
        for (int i = 0; i < n; ++i)
        {
            parent[i] = i;
        }
    }
    int find(int x) // ultimate parent
    {
        // path compression
        return parent[x] == x ? x : find(parent[x]);
    }
    int get_points(int n)
    {
        int amt = points[n];
        if (parent[n] == n)
        {
            return amt;
        }
        // we have to remove the extra points each node has
        amt += get_points(parent[n]) - extra_points[n];
        return amt;
    }
    void add_points(int n, int toadd)
    {
        // add in the ultimate parent
        // but we would store how much extra did the other parent had while merging
        // so that we dont count it in the final answer
        int top = find(n);
        points[top] += toadd;
    }
    bool unite(int x, int y)
    {
        int xr = find(x), yr = find(y);
        if (xr == yr)
        {
            return false;
        }
        if (size[xr] < size[yr])
        {
            swap(xr, yr);
        }
        parent[yr] = xr;
        size[xr] += size[yr];
        extra_points[yr] = points[xr];
        return true;
    }
    bool islink(int x, int y)
    {
        return find(x) == find(y);
    }
    int getsize(int x)
    {
        return size[find(x)];
    }
};
void solve()
{
    int n, q;
    cin >> n >> q;
    DSU dsu(n);
    while (q--)
    {
        string s;
        cin >> s;
        if (s == "add")
        {
            int n, points;
            cin >> n >> points;
            dsu.add_points(n - 1, points);
        }
        else if (s == "join")
        {
            int n, m;
            cin >> n >> m;
            dsu.unite(n - 1, m - 1);
        }
        else
        {
            int n;
            cin >> n;
            cout << dsu.get_points(n - 1) << endl;
        }
    }
    return;
}

signed main()
{
    NeedForSpeed;
    int t = 1;
    // cin >> t;
    while (t--)
    {
        solve();
    }
    return 0;
}