/**
 * Created at 01:34 on 2019-08-27
 */

import java.io.*;
import java.util.*;

public class Main {

  static FastScanner sc = new FastScanner();
  static Output out = new Output(System.out);

  static final int[] dx = {0, 1, 0, -1};
  static final int[] dy = {-1, 0, 1, 0};

  static final long MOD = (long) (1e9 + 7);
  static final long INF = Long.MAX_VALUE / 2;

  public static class Solver {
    public Solver() {

      int N = sc.nextInt();
      int M = sc.nextInt();

      int[] p = sc.nextIntArray(N, false);

      int[] index = new int[N];
      for (int i=0; i<N; i++) {
        index[p[i]-1] = i;
      }

      UnionFindTree uf = new UnionFindTree(N);

      for (int i=0; i<M; i++) {
        uf.union(sc.nextInt()-1, sc.nextInt()-1);
      }

      long ans = 0;
      for (int i=0; i<N; i++) {
        if (uf.same(i, index[i])) ans++;
      }

      out.println(ans);

    }


    class UnionFindTree {

        int[] parent; //インデックスにとノードを対応させ、そのルートノードのインデックスを格納
        int[] rank; //parentと同様に、木の高さを格納
        long[] size; //ルートの集合に含まれるノード数(ルート以外での値は不定)

        public UnionFindTree(int size) {
          this.parent = new int[size];
          this.rank = new int[size];
          this.size = new long[size];

          for (int i = 0; i < size; i++) {
            makeSet(i);
          }
        }

        public void makeSet(int i) {
          parent[i] = i;
          rank[i] = 0; //集合の高さ
          size[i] = 1;
        }

        public void union(int x, int y) {
          int xRoot = find(x);
          int yRoot = find(y);

          //xが属する木の方が大きい場合
          if (rank[xRoot] > rank[yRoot]) {
            parent[yRoot] = xRoot; //yの親をxに更新
            size[xRoot] += size[yRoot];
          } else if (rank[xRoot] < rank[yRoot]) {
            parent[xRoot] = yRoot;
            size[yRoot] += size[xRoot];
          } else if (xRoot != yRoot) {
            parent[yRoot] = xRoot;
            size[xRoot] += size[yRoot];
            rank[xRoot]++; //同じ高さの木がルートの子として着くから大きさ++;
          }

        }

        //引数の属する木のルートのidを返す
        public int find(int i) {
          if (i != parent[i]) {
            parent[i] = find(parent[i]);
          }
          return parent[i];
        }

        public long size(int i) {
          return size[find(i)];
        }

        //同じ木に属しているか
        public boolean same(int x, int y) {
          return find(x) == find(y);
        }

      }
  }

  public static void main(String[] args) {
    new Solver();
    out.flush();
  }

  static class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;

    private boolean hasNextByte() {
      if (ptr < buflen) {
        return true;
      } else {
        ptr = 0;
        try {
          buflen = in.read(buffer);
        } catch (IOException e) {
          e.printStackTrace();
        }
        if (buflen <= 0) {
          return false;
        }
      }
      return true;
    }

    private int readByte() {
      if (hasNextByte()) return buffer[ptr++];
      else return -1;
    }

    private static boolean isPrintableChar(int c) {
      return 33 <= c && c <= 126;
    }

    private void skipUnprintable() {
      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
    }

    public boolean hasNext() {
      skipUnprintable();
      return hasNextByte();
    }

    public String next() {
      if (!hasNext()) throw new NoSuchElementException();
      StringBuilder sb = new StringBuilder();
      int b = readByte();
      while (isPrintableChar(b)) {
        sb.appendCodePoint(b);
        b = readByte();
      }
      return sb.toString();
    }

    public long nextLong() {
      if (!hasNext()) throw new NoSuchElementException();
      long n = 0;
      boolean minus = false;
      int b = readByte();
      if (b == '-') {
        minus = true;
        b = readByte();
      }
      if (b < '0' || '9' < b) {
        throw new NumberFormatException();
      }
      while (true) {
        if ('0' <= b && b <= '9') {
          n *= 10;
          n += b - '0';
        } else if (b == -1 || !isPrintableChar(b)) {
          return minus ? -n : n;
        } else {
          throw new NumberFormatException();
        }
        b = readByte();
      }
    }

    public int nextInt() {
      return (int) nextLong();
    }

    public int[] nextIntArray(int N, boolean oneBased) {
      if (oneBased) {
        int[] array = new int[N + 1];
        for (int i = 1; i <= N; i++) {
          array[i] = sc.nextInt();
        }
        return array;
      } else {
        int[] array = new int[N];
        for (int i = 0; i < N; i++) {
          array[i] = sc.nextInt();
        }
        return array;
      }
    }

    public long[] nextLongArray(int N, boolean oneBased) {
      if (oneBased) {
        long[] array = new long[N + 1];
        for (int i = 1; i <= N; i++) {
          array[i] = sc.nextLong();
        }
        return array;
      } else {
        long[] array = new long[N];
        for (int i = 0; i < N; i++) {
          array[i] = sc.nextLong();
        }
        return array;
      }
    }
  }

  static class Output extends PrintWriter {

    public Output(PrintStream ps) {
      super(ps);
    }

    public void print(int[] a, String separator) {
      for (int i = 0; i < a.length; i++) {
        if (i == 0) print(a[i]);
        else print(separator + a[i]);
      }
      println();
    }

    public void print(long[] a, String separator) {
      for (int i = 0; i < a.length; i++) {
        if (i == 0) print(a[i]);
        else print(separator + a[i]);
      }
      println();
    }

    public void print(String[] a, String separator) {
      for (int i = 0; i < a.length; i++) {
        if (i == 0) print(a[i]);
        else print(separator + a[i]);
      }
      println();
    }

    public void print(ArrayList a, String separator) {
      for (int i = 0; i < a.size(); i++) {
        if (i == 0) print(a.get(i));
        else print(separator + a.get(i));
      }
      println();
    }
  }

}


Measured memory_bytes: 24856