#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;

#define lli long long int
#define REP(i, s, n) for (lli i = s; i < n; i++)
#define INF (1LL << 62)
#define DEBUG 0
#define mp(a, b) make_pair(a, b)
#define SORT(V) sort(V.begin(), V.end())
#define PI (3.141592653589794)
#define TO_STRING(VariableName) #VariableName
#define LOG1(x) \
    if (DEBUG) cout << TO_STRING(x) << "=" << x << " " << endl;
#define LOG2(x, y)                                                          \
    if (DEBUG)                                                              \
        cout << TO_STRING(x) << "=" << x << " " << TO_STRING(y) << "=" << y \
             << endl;
#define LOG3(x, y, z)                                                       \
    if (DEBUG)                                                              \
        cout << TO_STRING(x) << "=" << x << " " << TO_STRING(y) << "=" << y \
             << " " << TO_STRING(z) << "=" << z << endl;
#define LOG4(w, x, y, z)                                                      \
    if (DEBUG)                                                                \
        cout << TO_STRING(w) << "=" << w << " " << TO_STRING(x) << "=" << x   \
             << " " << TO_STRING(y) << "=" << y << " " << TO_STRING(z) << "=" \
             << z << endl;
#define LOG5(w, x, y, z, a)                                                   \
    if (DEBUG)                                                                \
        cout << TO_STRING(w) << "=" << w << " " << TO_STRING(x) << "=" << x   \
             << " " << TO_STRING(y) << "=" << y << " " << TO_STRING(z) << "=" \
             << z << " " << TO_STRING(a) << "=" << a << endl;
#define LOG6(w, x, y, z, a, b)                                                \
    if (DEBUG)                                                                \
        cout << TO_STRING(w) << "=" << w << " " << TO_STRING(x) << "=" << x   \
             << " " << TO_STRING(y) << "=" << y << " " << TO_STRING(z) << "=" \
             << z << " " << TO_STRING(a) << "=" << a << " " << TO_STRING(b)   \
             << "=" << b << endl;

#define overload6(a, b, c, d, e, f, g, ...) g
#define LOG(...) \
    overload6(__VA_ARGS__, LOG6, LOG5, LOG4, LOG3, LOG2, LOG1)(__VA_ARGS__)

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;
}

mt19937 engine;
std::chrono::system_clock::time_point start, endTime;

std::ostream &operator<<(std::ostream &dest, __int128_t value) {
    std::ostream::sentry s(dest);
    if (s) {
        __uint128_t tmp = value < 0 ? -value : value;
        char buffer[128];
        char *d = std::end(buffer);
        do {
            --d;
            *d = "0123456789"[tmp % 10];
            tmp /= 10;
        } while (tmp != 0);
        if (value < 0) {
            --d;
            *d = '-';
        }
        int len = std::end(buffer) - d;
        if (dest.rdbuf()->sputn(d, len) != len) {
            dest.setstate(std::ios_base::badbit);
        }
    }
    return dest;
}

__int128 parse(string &s) {
    __int128 ret = 0;
    for (int i = 0; i < s.length(); i++) {
        if ('0' <= s[i] && s[i] <= '9') {
            ret = 10 * ret + s[i] - '0';
        }
    }
    return ret;
}
// checker https://atcoder.jp/contests/abc264/tasks/abc264_e

struct UnionFind {
    vector<int> par;  // par[i]:iの親の番号　(例) par[3] = 2 : 3の親が2
    vector<bool> isOk;
    vector<lli> siz;  // 素集合のサイズを表す配列(1 で初期化)
    lli N;

    UnionFind(int N)
        : par(N), isOk(N), siz(N) {  // 最初は全てが根であるとして初期化
        for (int i = 0; i < N; i++) {
            par[i] = i;
            isOk[i] = false;
            siz[i] = 1;
        }

        this->N = N;
    }

    int root(
        int x) {  // データxが属する木の根を再帰で得る：root(x) = {xの木の根}
        if (par[x] == x) return x;
        return par[x] = root(par[x]);
    }

    void setOk(lli i) { isOk[i] = isOk[root(i)] = true; }

    bool isCheckOk(lli i) { return isOk[root(i)]; }
    void unite(int x, int y) {  // xとyの木を併合
        int rx = root(x);       // xの根をrx
        int ry = root(y);       // yの根をry
        if (rx == ry) return;  // xとyの根が同じ(=同じ木にある)時はそのまま

        if (siz[rx] < siz[ry]) swap(rx, ry);
        siz[rx] += siz[ry];
        par[ry] =
            rx;  // xとyの根が同じでない(=同じ木にない)時：xの根rxをyの根ryにつける
        if (isOk[rx] || isOk[ry]) {
            isOk[ry] = true;
            isOk[rx] = true;
        }
    }

    bool same(int x, int y) {  // 2つのデータx, yが属する木が同じならtrueを返す
        int rx = root(x);
        int ry = root(y);
        return rx == ry;
    }
    lli size(lli x) { return siz[root(x)]; }
};

void solve() {
    lli N, M;
    cin >> N >> M;

    UnionFind uf(N);
    vector<lli> C(N);
    REP(i, 0, N) cin >> C[i];
    REP(i, 0, M) {
        lli u, v;
        cin >> u >> v;
        u--;
        v--;
        if (C[u] == C[v]) {
            uf.unite(u, v);
        }
    }
    map<lli, set<lli>> cs;

    REP(i, 0, N) { cs[C[i]].insert(uf.root(i)); }

    lli ans = 0;
    for (auto &e : cs) {
        ans += e.second.size() - 1;
    }
    cout << ans << endl;
}

// Generated by 2.12.0 https://github.com/kyuridenamida/atcoder-tools  (tips:
// You use the default template now. You can remove this line by using your
// custom template)
int main() {
    lli n = 1;
    // cin>>n;
    while (n--) solve();
    return 0;
}

struct Setup {
    Setup() {
        cin.tie(0);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(15);
    }
} __Setup;