N, M, T = map(int, input().split())
A = list(map(int, input().split()))

cnt = [0]*N
for i in range(M):
  cnt[A[i]-1] += 1
cnt.sort(reverse=1)

def f(x):
  stk = 0
  for i in range(N):
    if cnt[i] > x:
      stk += cnt[i] - x
    else:
      y = x - cnt[i]
      stk -= y//T
  return stk <= 0

r = 1<<60
l = -1
while r - l > 1:
  m = (r + l)//2
  if f(m):
    r = m
  else:
    l = m

print(r)