local UF = {}
UF.create = function(self, n)
  self.parent = {}
  for i = 1, n do
    self.parent[i] = i
  end
end
UF.getroot = function(self, idx)
  local parent = self.parent
  local idx_update = idx
  while parent[idx] ~= idx do
    idx = parent[idx]
  end
  while parent[idx_update] ~= idx do
    parent[idx_update], idx_update = idx, parent[idx_update]
  end
  return idx
end
UF.unite = function(self, a, b)
  local ra = self:getroot(a)
  local rb = self:getroot(b)
  self.parent[b], self.parent[rb] = ra, ra
end
UF.new = function(n)
  local obj = {}
  setmetatable(obj, {__index = UF})
  obj:create(n)
  return obj
end

local n, m = io.read("*n", "*n")
local c = {}
local cg = {}
for i = 1, n do
  c[i] = io.read("*n")
  if not cg[c[i]] then
    cg[c[i]] = {}
  end
end
local uf = UF.new(n)

for i = 1, m do
  local a, b = io.read("*n", "*n")
  if c[a] == c[b] then
    uf:unite(a, b)
  end
end
for i = 1, n do
  local r = uf:getroot(i)
  cg[c[i]][r] = true
end
local ans = 0
for ci, tbl in pairs(cg) do
  local cnt = 0
  for key, val in pairs(tbl) do
    cnt = cnt + 1
  end
  ans = ans + cnt - 1
end
print(ans)