#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <string>
#include <math.h>
#include <iomanip>
#include <limits>
#include <list>
#include <queue>
#include <tuple>
#include <map>
#include <stack>
#include <set>
using namespace std;
#define fast_io ios_base::sync_with_stdio (false) ; cin.tie(0) ; cout.tie(0) ;
#define MOD (long long int)(1e9+7)
#define ll long long int
#define rep(i,n) for(int i=0; i<(int)(n); i++)
#define reps(i,n) for(int i=1; i<=(int)(n); i++)
#define REP(i,n) for(int i=n-1; i>=0; i--)
#define REPS(i,n) for(int i=n; i>0; i--)
#define INF (int)(1123456789)
#define LINF (long long int)(112345678901234567)
#define chmax(a, b) a = (((a)<(b)) ? (b) : (a))
#define chmin(a, b) a = (((a)>(b)) ? (b) : (a))
#define all(v) v.begin(), v.end()

typedef pair<int, int> Pii;
typedef pair<ll, ll> Pll;

ll mpow(ll a, ll b){
  if(b==0) return 1;
  else if(b%2==0){ll memo = mpow(a,b/2); return memo*memo%MOD;}
  else return mpow(a,b-1) * a % MOD;
}
ll lpow(ll a, ll b){
  if(b==0) return 1;
  else if(b%2==0){ll memo = lpow(a,b/2); return memo*memo;}
  else return lpow(a,b-1) * a;
}
ll gcd(ll a, ll b){
  if(b==0) return a;
  else return gcd(b, a%b);
}
vector<ll> kaijo_memo;
ll kaijo(ll n){
  if(kaijo_memo.size() > n) return kaijo_memo[n];
  if(kaijo_memo.size() == 0) kaijo_memo.push_back(1);
  while(kaijo_memo.size() <= n) kaijo_memo.push_back(kaijo_memo[kaijo_memo.size()-1] * kaijo_memo.size() % MOD);
  return kaijo_memo[n];
}
vector<ll> gyaku_kaijo_memo;
ll gyaku_kaijo(ll n){
  if(gyaku_kaijo_memo.size() > n) return gyaku_kaijo_memo[n];
  if(gyaku_kaijo_memo.size() == 0) gyaku_kaijo_memo.push_back(1);
  while(gyaku_kaijo_memo.size() <= n) gyaku_kaijo_memo.push_back(gyaku_kaijo_memo[gyaku_kaijo_memo.size()-1] * mpow(gyaku_kaijo_memo.size(), MOD-2) % MOD);
  return gyaku_kaijo_memo[n];
}

ll nCr(ll n, ll r){
  if(n == r) return 1;//0個の丸と-1個の棒みたいな時に時に効く？不安.
  if(n < r || r < 0) return 0;
  ll ret = 1;
  ret *= kaijo(n); ret %= MOD;
  ret *= gyaku_kaijo(r); ret %= MOD;
  ret *= gyaku_kaijo(n-r); ret %= MOD;
  return ret;
}

int parent[(int)1e5+3];
vector<ll> costs[(int)1e5+3];
int find(int a){
  if(parent[a] == a){
    return a;
  }else{
    return parent[a] = find(parent[a]);
  }
}

void unite(int a, int b){
  int pa = find(a);
  int pb = find(b);
  parent[pa] = pb;
}

int main(void){
  fast_io
  cout<<fixed<<setprecision(15);

  int n,m;cin>>n>>m;
  vector<ll> A;
  rep(i,n){
    int a;cin>>a;
    A.push_back(a);
    parent[i] = i;
  }

  rep(i,m){
    int x,y;cin>>x>>y;
    unite(x,y);
  }

  rep(i,n){
    int p = find(i);
    costs[p].push_back(A[i]);
  }

  vector<ll> hoge;
  ll ans = 0;
  ll num = 0;
  ll renketu = 0;
  rep(i,n){
    int p = find(i);
    if(i!=p) continue;

    sort(all(costs[p]));
    renketu++;
    num++;
    ans += costs[p][0];
    rep(j, costs[p].size()){
      if(j==0) continue;
      hoge.push_back(costs[p][j]);
    }
  }
  if(renketu == 1){
    cout<<0<<endl;
    return 0;
  }

  sort(all(hoge));
  int hi = 0;
  while(renketu - num/2 >= 2){
    if(hi >= hoge.size()){
      cout<<"Impossible"<<endl;
      return 0;
    }

    num++;
    ans += hoge[hi];
    hi++;
  }
  cout<<ans<<endl;

  return 0;
}

Measured memory_bytes: 6900