n, m, k = read_line.split.map(&.to_i)
inc = Array.new(n, 0)
outc = Array.new(n, 0)
m.times do
  a, b = read_line.split.map { |v| v.to_i - 1 }
  inc[b] += 1
  outc[a] += 1
end
ics = [] of Int32
ocs = [] of Int32
n.times do |i|
  if outc[i] > 0
    ics << inc[i]
  else
    ocs << inc[i]
  end
end
ocs.sort!
while ics.size <= k
  ics << ocs.pop
end
puts ics.sum { |v| v >= k ? 0i64 : k.to_i64 - v }