from collections import defaultdict,deque
N,M=map(int,input().split())
C=list(map(int,input().split()))
G=defaultdict(list)
for i in range(M):
    u,v=map(int,input().split())
    if(C[u-1]==C[v-1]):
        G[u].append(v)
        G[v].append(u)
#連結成分の個数-色の種類数
T=1
c=0
seen=[False]*(N+1)
while T<=N:
    que=deque([T])
    seen[T]=True
    while len(que):
        p=que.popleft()
        for q in G[p]:
            if(not seen[q]):
                seen[q]=True
                que.append(q)
    while T<=N and seen[T]:
        T+=1
    c+=1
print(c-len(set(C)))