#include <bits/stdc++.h>

int main() {
  int N, M;
  std::cin >> N >> M;
  std::vector<int> C(N+1);
  std::vector<std::vector<int>> G(N+1);
  for (int i = 1; i <= N; ++i)
    std::cin >> C[i];
  while (M--) {
    int u, v;
    std::cin >> u >> v;
    if (C[u] == C[v]) {
      G[u].push_back(v);
      G[v].push_back(u);
    }
  }

  std::vector<int> groups(N+1);
  std::vector<bool> done(N+1, false);
  for (int s = 1; s <= N; ++s)
    if (!done[s]) {
      std::vector<int> bfs;
      bfs.reserve(N);
      bfs.push_back(s);
      done[s] = true;
      for (auto u = bfs.begin(); u != bfs.end(); ++u)
        for (const int &v : G[*u])
          if (!done[v])
            bfs.push_back(v), done[v] = true;
      ++groups[C[s]];
    }

  int answer{};
  for (int c = 1; c <= N; ++c)
    if (groups[c] > 1)
      answer += groups[c] - 1;
  std::cout << answer << '\n';
}