class UnionFind:
    def __init__(self, N):
        self.p = [-1] * N

    def find(self, x):
        y = self.p[x]
        while y >= 0:
            x = y
            y = self.p[y]
        return x

    def unite(self, x, y):
        x, y = self.find(x), self.find(y)
        if x == y:
            return
        if -self.p[x] < -self.p[y]:
            x, y = y, x
        self.p[x] += self.p[y]
        self.p[y] = x


N, M = map(int, input().split())
uf = UnionFind(N)
ans = 0
C = list(map(int, input().split()))
for _ in range(M):
    v, w = map(int, input().split())
    v -= 1
    w -= 1
    if C[v] != C[w]:
        continue
    uf.unite(v, w)
d = {}
for i, c in enumerate(C):
    if c not in d:
        d[c] = []
    d[c].append(i)

for c in d:
    S = set()
    for i in d[c]:
        S.add(uf.find(i))
    ans += len(S) - 1
print(ans)