//header
#ifdef LOCAL
    #include "cxx-prettyprint-master/prettyprint.hpp"
    #define print(x) cout << x << endl
#else
    #define print(...) 42
#endif
    #pragma GCC optimize("Ofast")
    #include <bits/stdc++.h>
    //types
    using namespace std;
    using ll = long long;
    typedef pair < ll , ll >P;
    typedef vector<ll> vl;
    template< typename T >
    using Matrix = vector< vector< T > >;
    template <std::uint_fast64_t Modulus> class modint {
        using u64 = std::uint_fast64_t;

        public:
        u64 a;

        constexpr modint(const u64 x = 0) noexcept : a(x % Modulus) {}
        constexpr u64 &value() noexcept { return a; }
        constexpr const u64 &value() const noexcept { return a; }
        constexpr modint operator+(const modint rhs) const noexcept {
            return modint(*this) += rhs;
        }
        constexpr modint operator-(const modint rhs) const noexcept {
            return modint(*this) -= rhs;
        }
        constexpr modint operator*(const modint rhs) const noexcept {
            return modint(*this) *= rhs;
        }
        constexpr modint operator/(const modint rhs) const noexcept {
            return modint(*this) /= rhs;
        }
        constexpr modint &operator+=(const modint rhs) noexcept {
            a += rhs.a;
            if (a >= Modulus) {
            a -= Modulus;
            }
            return *this;
        }
        constexpr modint &operator-=(const modint rhs) noexcept {
            if (a < rhs.a) {
            a += Modulus;
            }
            a -= rhs.a;
            return *this;
        }
        constexpr modint &operator*=(const modint rhs) noexcept {
            a = a * rhs.a % Modulus;
            return *this;
        }
        constexpr modint &operator/=(modint rhs) noexcept {
            u64 exp = Modulus - 2;
            while (exp) {
            if (exp % 2) {
                *this *= rhs;
            }
            rhs *= rhs;
            exp /= 2;
            }
            return *this;
        }
        };
    //abbreviations
    #define all(x) (x).begin(), (x).end()
    #define reverse(x) (x).rbegin(), (x).rend()
    #define rep2(i,a,b) for(ll i=(a);i<(b);++i)
    #define rep(i,n) for(ll i=0;i<(n);++i)
    #define SZ(x) ((ll)(x).size())
    #define sum(x) accumulate(begin(x), end(x), 0LL)//?
    #define pb(x) push_back(x)
    //functions
    ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
    template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
    template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
    template< typename T >
    T mod_pow(T x, T n, const T &p) {
        T ret = 1;
        while(n > 0) {
            if(n & 1) (ret *= x) %= p;
            (x *= x) %= p;
            n >>= 1;
        }
        return ret;
    }
    uint64_t my_rand(void) {
        static uint64_t x = 88172645463325252ULL;
        x = x ^ (x << 13); x = x ^ (x >> 7);
        return x = x ^ (x << 17);
    }

//constant
#define INF 1'010'000'000'000'000'017LL
#define mod 1000000007LL
#define eps 0.0001
//library
struct UnionFind {
    vector< int > data;

    UnionFind(int sz) {
        data.assign(sz, -1);
    }

    bool unite(int x, int y) {
        x = find(x), y = find(y);
        if(x == y) return (false);
        if(data[x] > data[y]) swap(x, y);
        data[x] += data[y];
        data[y] = x;
        return (true);
    }

    int find(int k) {
        if(data[k] < 0) return (k);
        return (data[k] = find(data[k]));
    }

    int size(int k) {
        return (-data[find(k)]);
    }
};
//main
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout<<fixed<<setprecision(20);
    ll N, M;
    cin >> N >> M;
    UnionFind U(N);
    vl a(N);
    multiset<ll> s;
    rep(i, N){
        cin >> a[i];
        s.insert(a[i]);
    }
    rep(i, M){
        int x, y;
        cin >> x >> y;
        U.unite(x, y);
    }
    map<int, multiset<ll>> trees;
    rep(i, N){
        trees[U.find(i)].insert(a[i]);
    }
    ll ans = 0;
    ll size = SZ(trees);
    for(auto t:trees){
        ans+=*begin(t.second);
        s.erase(s.lower_bound(*begin(t.second)));
    }
    if(SZ(trees) == 1){
        cout << 0 << endl;
        return 0;
    }
    auto iter = begin(s);
    if(SZ(s)<size-2){
        cout<<"Impossible"<<endl;
        return 0;
    }
    rep(i, size-2){
        ans+=*iter;
        iter++;
    }
    cout << ans << endl;
}


Measured memory_bytes: 20224