class unif:
  def __init__(self,n):
    self.pare=[-1]*n
    self.size=[1]*n
  def root(self,x):
    while self.pare[x]!=-1:
      x=self.pare[x]
    return x
  def unite(self,u,v):
    rootu=self.root(u)
    rootv=self.root(v)
    if rootu!=rootv:
      if self.size[rootu]>=self.size[rootv]:
        self.pare[rootv]=rootu
        self.size[rootu]+=self.size[rootv]
      else:
        self.pare[rootu]=rootv
        self.size[rootv]+=self.size[rootu]
  def same(self,s,t):
    return self.root(s)==self.root(t)
N,M=map(int,input().split())
C=list(map(int,input().split()))
R=[[] for i in range(N)]
Z=unif(N)
for i in range(N):
  R[C[i]-1].append(i)
G=[[] for i in range(N)]
for i in range(M):
  a,b=map(int,input().split())
  if C[a-1]==C[b-1]:
    Z.unite(a-1,b-1)
result=0
for i in range(N):
  if len(R[i])==0:
    continue
  A=set()
  for j in R[i]:
    A.add(Z.root(j))
  result+=len(A)-1
print(result)