CUBE-T121: COI Great Raid

#include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef long long lli;

typedef struct edge{
    int u;
    int v;
    int w;
    bool operator < (const edge &rhs)const{
        return w > rhs.w;
    }
}edge;

priority_queue<edge> adj;
vector<int> power;
vector<int> parent;
vector<int> ranks;
int nv, ne;

void PrintPower(){
    for(int i = 1; i <= nv; ++i){
        cout << power[i] << " ";
    }
    cout << "\n";
    return;
}

int FindDSet(int x){
    if(parent[x] == x){
        return x;
    } else {
        return parent[x] = FindDSet(parent[x]);
    }
}

void UnionDSet(int f, int s){
    int x = FindDSet(f);
    int y = FindDSet(s);
    if(ranks[x] > ranks[y]){
        parent[y] = x;
    } else {
        parent[x] = y;
        if(ranks[x] == ranks[y]){
            ++ranks[y];
        }
    }
    return;
}

lli Kruskal(){
    lli sum = 0;
    while(!adj.empty()){
        edge t = {adj.top().u, adj.top().v, adj.top().w};
        adj.pop();
        if(FindDSet(t.u) != FindDSet(t.v)){
            sum += t.w;
            UnionDSet(t.u, t.v);
        }
    }
    return sum;
}

int main(){

    int x, u, v;

    scanf("%d", &nv);
    power.assign(nv + 1, 0);
    parent.assign(nv + 1, 0);
    ranks.assign(nv + 1, 0);
    for(int i = 1; i <= nv; ++i){
        scanf("%d", &x);
        power[i] = x;
        parent[i] = i;
    }

    scanf("%d", &ne);
    for(int i = 0; i < ne; ++i){
        scanf("%d %d", &u, &v);
        adj.push({u, v, power[u] + power[v]});
    }

    cout << Kruskal();

    return 0;
}