# import pypyjit;pypyjit.set_param("max_unroll_recursion=-1")
import os
import sys

# from bisect import *
from collections import *

# from datetime import *
# from decimal import *  # PyPyだと遅い
# from heapq import *
# from itertools import *
# from math import gcd, lcm
# from random import *
# from string import *

# import numpy as np
# from atcoder.dsu import *
# from atcoder.segtree import *
# from more_itertools import *
# from sortedcontainers import *

# sys.setrecursionlimit(10**7)  # PyPyは呪文を付ける
# sys.set_int_max_str_digits(0)
INF = 1 << 61
MOD = 998244353
# MOD = 10**9 + 7
IS_ATCODER = os.getenv("ATCODER", 0)

File = sys.stdin


def input():
    return File.readline().replace("\n", "")


# ///////////////////////////////////////////////////////////////////////////
def bfs(G, start):
    """
    グラフで幅優先探索をする関数
    seenを集合、distを辞書で管理
    配列で管理するより遅め

    引数:
    G (defaultdict): グラフ
    start (int): 始点

    戻り値:
    dist (dict): 始点からの距離
    """
    que = deque()
    dist = {}

    global seen
    que.append(start)
    seen.add(start)
    dist[start] = 0
    while que:
        for _ in range(len(que)):
            pop = que.popleft()
            for i in G[pop]:
                if i not in seen and C[i] == C[pop]:
                    seen.add(i)
                    dist[i] = dist.get(pop, 0) + 1
                    que.append(i)

    return dist


N, M = map(int, input().split())
C = list(map(int, input().split()))
edges = [list(map(int, input().split())) for _ in range(M)]

G = [set() for _ in range(N)]
for i, j in edges:
    G[i - 1].add(j - 1)
    G[j - 1].add(i - 1)

color = defaultdict(list)
for i, j in enumerate(C):
    color[j].append(i)

ans = 0
for i in color.keys():
    seen = set()
    c = 0
    for j in color[i]:
        if j in seen:
            continue
        c += 1
        bfs(G, j)
    ans += c - 1

print(ans)