package main

import . "fmt"
import . "os"
import bf "bufio"

func main() {
	rd:=bf.NewReader(Stdin)
	var n,m int
	Fscan(rd,&n,&m)
	cs:=make([]int,n)
	for i:=range cs {
		Fscan(rd,&cs[i])
	}
	t:=make([][]int,n)
	for ;m>0;m-- {
		var u,v int
		Fscan(rd,&u,&v)
		u--
		v--
		t[u]=append(t[u],v)
		t[v]=append(t[v],u)
	}
	visited:=make([]bool,n)
	g:=make(map[int]int)
	for i,c:=range cs {
		if visited[i] {
			continue
		}
		g[c]++
		visited[i]=true
		p:=t[i][:]
		for len(p)>0 {
			e:=p[len(p)-1]
			p=p[:len(p)-1]
			if cs[e]!=c||visited[e] {
				continue
			}
			visited[e]=true
			p=append(p,t[e]...)
		}
	}
	var ans int
	for _,c:=range g {
		if c>0 {
			ans+=c-1
		}
	}
	Println(ans)
}