#include <bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define rrep(i,n) for(int (i)=((n)-1);(i)>=0;(i)--)
#define itn int
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
using P = pair <int,int>;
using WeightedGraph = vector<vector <P>>; //to cost
using UnWeightedGraph = vector<vector<int>>;
const long long INF = 1LL << 60;
const int MOD = 1000000007;
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
#define DUMPOUT cerr
#define repi(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++)
template <typename T, typename U>
istream &operator>>(istream &is, pair<T,U> &p_var) {
    is >> p_var.first >> p_var.second;
    return is;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
    for (T &x : vec) is >> x;
    return is;
}
template <typename T>
istream &operator>>(istream &is, vector<vector<T>> &df) {
    for(int i=0;i<df.size();i++)for(int j=0;j<df[i].size();j++)
    is >> df[i][j];
    return is;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, pair<T, U> &pair_var) {
    DUMPOUT<<'{';
    os << pair_var.first;
    DUMPOUT<<',';
    os << " "<< pair_var.second;
    DUMPOUT<<'}';
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, vector<T> &vec) {
    DUMPOUT<<'[';
    for (int i = 0; i < vec.size(); i++) 
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
    DUMPOUT<<']';
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, vector<vector<T>> &df) {
  for (auto& vec : df) os<<vec;
  return os;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, map<T, U> &map_var) {
    DUMPOUT << "{";
    repi(itr, map_var) {
        os << *itr;
        itr++;
        if (itr != map_var.end()) DUMPOUT << ", ";
        itr--;
    }
    DUMPOUT << "}";
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, set<T> &set_var) {
    DUMPOUT << "{";
    repi(itr, set_var) {
        os << *itr;
        itr++;
        if (itr != set_var.end()) DUMPOUT << ", ";
        itr--;
    }
    DUMPOUT << "}";
    return os;
}
void print() {cout << endl;}
template <class Head, class... Tail>
void print(Head&& head, Tail&&... tail) {
  cout << head;
  if (sizeof...(tail) != 0) cout << " ";
  print(forward<Tail>(tail)...);
}
void dump_func() {DUMPOUT << '#'<<endl;}
template <typename Head, typename... Tail>
void dump_func(Head &&head, Tail &&... tail) {
    DUMPOUT << head;
    if (sizeof...(Tail) > 0) DUMPOUT << ", ";
    dump_func(std::move(tail)...);
}
#ifdef DEBUG_
#define DEB
#define dump(...)                                                              \
    DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                            \
            << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]"        \
            << endl                                                            \
            << "    ",                                                         \
        dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define dump(...)
#endif
struct UnionFind {
    vector<int> par; 

    UnionFind(int N) : par(N) { 
        for(int i = 0; i < N; i++) par[i] = i;
    }

    int root(int x) { 
        if (par[x] == x) return x;
        return par[x] = root(par[x]);
    }

    void unite(int x, int y) { 
        int rx = root(x); 
        int ry = root(y); 
        if (rx == ry) return; 
        par[rx] = ry; 
    }

    bool same(int x, int y) { 
        int rx = root(x);
        int ry = root(y);
        return rx == ry;
    }
};
signed main(void) { cin.tie(0); ios::sync_with_stdio(false);
    int n,m; cin>>n>>m;
    vector <int> a(n);
    cin>>a;
    UnionFind uf(n);
    rep(i,m){
        int x,y; cin>>x>>y;
        uf.unite(x, y);
    }
    priority_queue <int, vector <int>, greater <int>> pq;
    map <int,int> ma;
  
    rep(i,n){
    
        int rt = uf.root(i);
        if(ma[rt] > a[i] || ma[rt]==0){
            if(ma[rt]!=0) pq.push(ma[rt]);
            ma[rt] = a[i];
        }else pq.push(a[i]);
        
    }
   
    if(ma.size() == 1) {
        print(0);
        return 0;
    }
    int ans = 0;

    vector <bool> done(n);
    rep(i,n){
        int rt = uf.root(i);
        if(!done[rt]){
            done[rt]=true;
            ans += ma[rt];
        }
    }
    
    rep(i,2*(n-m-1)-ma.size()){
        if(pq.size()==0){
            print("Impossible");
            return 0;
        }
        ans += pq.top(); pq.pop();
    }
    print(ans);
}


Measured memory_bytes: 8064