#緑以下G

#UnionFind
class UnionFind:
    def __init__(self,N): self._parent=[-1 for i in[0]*N]
    def find(self,v):  #頂点vの親を探し、経路圧縮する
        vertices=[]
        while self._parent[v]>=0: vertices.append(v);v=self._parent[v]
        for i in vertices: self._parent[i]=v
        return v
    def unite(self,x,y):  #頂点xとyを併合し、併合の有無を返す
        x,y = self.find(x),self.find(y)
        if x==y: return 0
        if self._parent[x]>self._parent[y]: x,y=y,x  #負値で管理
        self._parent[x]+=self._parent[y]; self._parent[y]=x; return 1
    def same(self,x,y):return self.find(x)==self.find(y)   #xとyは同一集合か返す
    def size(self,x):  return -self._parent[self.find(x)]  #xの集合のサイズを求める


from collections import defaultdict

#入力受取
N,M = map(int,input().split())
C = list(map(int,input().split()))
UF = UnionFind(N)
for _ in range(M):
    u,v = map(lambda x: int(x)-1,input().split())
    if C[u] == C[v]: UF.unite(u,v)

#色ごとに連結判定
D = defaultdict(list)
for i,c in enumerate(C): D[c].append(i)
ans = 0
for c in D.keys():
    base = D[c][0]
    for i in D[c]:
        if not UF.same(base,i): UF.unite(base,i); ans += 1
print(ans)