import collections
from collections import defaultdict
class UnionFind():
    def __init__(self):
        '''
        unionfind経路圧縮あり,要素にtupleや文字列可,始めに要素数指定なし
        '''
        self.parents = dict()                                      # {子要素:親ID,}
        self.members_set = collections.defaultdict(lambda : set()) # keyが根でvalueが根に属する要素要素(tupleや文字列可)
        self.roots_set = set()                                     # 根の集合(tupleや文字列可)
        self.key_ID = dict()                                       # 各要素にIDを割り振る
        self.ID_key = dict()                                       # IDから要素名を復元する
        self.cnt = 0                                               # IDのカウンター

    def dictf(self,x): # 要素名とIDをやり取りするところ
        if x in self.key_ID:
            return self.key_ID[x]
        else:
            self.cnt += 1
            self.key_ID[x] = self.cnt
            self.parents[x] = self.cnt
            self.ID_key[self.cnt] = x
            self.members_set[x].add(x)
            self.roots_set.add(x)
            return self.key_ID[x]

    def find(self, x):
        ID_x = self.dictf(x)
        if self.parents[x] == ID_x:
            return x
        else:
            self.parents[x] = self.key_ID[self.find(self.ID_key[self.parents[x]])]
            return self.ID_key[self.parents[x]]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)
        if self.parents[x] > self.parents[y]:
            x, y = y, x
        if x == y:
            return
        for i in self.members_set[y]:
            self.members_set[x].add(i)
        self.members_set[y] = set()
        self.roots_set.remove(y)
        self.parents[y] = self.key_ID[x]

    def size(self, x):#xが含まれる集合の要素数
        return len(self.members_set[self.find(x)])

    def same(self, x, y):#同じ集合に属するかの判定
        return self.find(x) == self.find(y)

    def members(self, x):#xを含む集合の要素
        return self.members_set[self.find(x)]

    def roots(self):#根の要素
        return self.roots_set

    def group_count(self):#根の数
        return len(self.roots_set)

    def all_group_members(self):#根とその要素
        return {r: self.members_set[r] for r in self.roots_set}

N, M = map(int, input().split())

C = list(map(int, input().split()))
colors = collections.defaultdict(list)
for i in range(N):
  colors[C[i]].append(i + 1)
uf = UnionFind()
for i in range(M):
  u, v = map(int, input().split())
  if C[u - 1] == C[v - 1]:
    uf.union(u, v)

ans = 0
for i in colors.keys():
  m = colors[i][0]
  for n in colors[i]:
    if not uf.same(n, m):
      uf.union(n, m)
      ans += 1
print(ans)