/**
 *    author:  otera    
**/
#include<iostream>
#include<string>
#include<cstdio>
#include<cstring>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<deque>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
#include<cassert>
using namespace std;

typedef long long ll;
typedef unsigned long long ul;
typedef unsigned int ui;
typedef long double ld;
const int inf=1e9+7;
const ll INF=1LL<<60 ;
const ll mod=1e9+7 ;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<int, int> P;
typedef pair<ld, ld> LDP;
typedef pair<ll, ll> LP;
#define fr first
#define sc second
#define all(c) c.begin(),c.end()
#define pb push_back
#define debug(x)  cerr << #x << " = " << (x) << endl;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
#define int long long

struct UnionFind {
    vector<int> par, w;
    
    UnionFind(int n) : par(n, -1), w(n, 0) { }
    void init(int n) { par.assign(n, -1); w.assign(n, 0); }
    
    int root(int x) {
        if (par[x] < 0) return x;
        else return par[x] = root(par[x]);
    }
    
    bool issame(int x, int y) {
        return root(x) == root(y);
    }
    
    bool merge(int x, int y) {
        x = root(x); y = root(y);
        if (x == y) {
            ++w[x];
            return false;
        }
        if (par[x] > par[y]) swap(x, y); // merge technique
        par[x] += par[y];
        par[y] = x;
        w[x] += w[y];
        ++w[x];
        return true;
    }
    
    int size(int x) {
        return -par[root(x)];
    }
 
    int wei(int x) {
        return w[root(x)];
    }
};

void solve() {
	int n, m; cin >> n >> m;
    vector<int> a(n);
    int sum = 0;
    rep(i, n) {
        cin >> a[i];
        sum += a[i];
    }
    vector<int> g[100100];
    UnionFind uf(n);
    rep(i, m) {
        int x, y; cin >> x >> y;
        g[x].pb(y);
        g[y].pb(x);
        uf.merge(x, y);
    }
    set<int> se;
    rep(i, n) {
        se.insert(uf.root(i));
    }
    int cnt = se.size();
    if(cnt == 1) {
        cout << 0 << endl;
        return;
    }
    if((cnt - 1) * 2 <= n) {
        priority_queue<int> pque;
        map<int, vector<int>> mp;
        rep(i, n) {
            mp[uf.root(i)].pb(a[i]);
        }
        for(auto& p: mp) {
            auto s = p.sc;
            sort(all(s));
            for(int i = 1; i < s.size(); ++i) {
                pque.push(s[i]);
            }
        }
        rep(i, n - (cnt - 1) * 2) {
            sum -= pque.top();
            pque.pop();
        }
        cout << sum << endl;
    } else {
        cout << "Impossible" << endl;
    }
}

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed << setprecision(10);
	//init();
	//int t; cin >> t; rep(i, t)solve();
	solve();
	//cout << "finish" << endl;
    return 0;
}

Measured memory_bytes: 16000