N,M,T=map(int,input().split())
A=list(map(int,input().split()))
l,r=1,10**17
while True:
  m=(l+r)//2
  v=[0]*(N+1)
  a=0
  for i in range(M):
    x=A[i]
    if v[x]+1<=m:
      v[x]+=1
    else:
      a+=1
  rest=0
  for i in range(1,N+1):
    t=m-v[i]
    rest+=t//T
  if rest>=a:
    r=m
  else:
    l=m+1
  if l==r:
    break
print(l)