def INT():
    return int(input())


def MI():
    return map(int, input().split())


def LI():
    return list(map(int, input().split()))


class UnionFind:
    def __init__(self, N):
        self.root = [_ for _ in range(N)]
        self.rank = [0] * N
        self.size = [1] * N

    def find(self, x):
        if self.root[x] == x:
            return x
        else:
            # 根を予め取得し,経路圧縮する
            self.root[x] = self.find(self.root[x])
            return self.root[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return
        else:
            if self.rank[x] > self.rank[y]:
                self.size[x] += self.size[y]
                self.root[y] = x
            else:
                self.size[y] += self.size[x]
                self.root[x] = y
                if self.rank[x] == self.rank[y]:
                    self.rank[y] += 1

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def getSizeOfSet(self, x):
        return self.size[self.find(x)]


N, M = MI()
C = LI()
dsu = UnionFind(N)
for _ in range(M):
    u, v = MI()
    u -= 1
    v -= 1
    if C[u] == C[v]:
        dsu.union(u, v)

cl = [[] for _ in range(N)]
for i in range(N):
    cl[C[i] - 1].append(i)

ans = 0
for i in range(N):
    if len(cl[i]) <= 1:
        continue
    root_c = set()
    for c in cl[i]:
        root_c.add(dsu.root[c])
    ans += len(root_c) - 1

print(ans)