LeetCode: Redundant Connection

class Solution {
public:
    int parent[1010];

    int root(int u){
        if(parent[u] == u) return u;
        return parent[u] = root(parent[u]);
    }

    void mrg(int u, int v){
        u = root(u);
        v = root(v);
        parent[v] = u;
    }

    vector<int> findRedundantConnection(vector<vector<int>>& edges){

        for(int u=1;u<=1000;u++)
            parent[u] = u;

        int a = -1, b = -1;
        for(auto e: edges){
            int u = e[0];
            int v = e[1];
            if(root(u) == root(v))
                a = u, b = v;
            mrg(u, v);
        }
        return {a, b};
    }
};