# https://oj.uz/problem/view/CEOI12_jobs
from collections import defaultdict
n, d, m = map(int, input().split())
requests_by_day = defaultdict(list)
for req_iq, day in enumerate(map(int, input().split())):
requests_by_day[day].append(req_iq + 1)
requests = sorted(requests_by_day.items())
# does `mid` number of machines work?
def ok(mid):
requests_here = [list(req) for req in requests]
schedule = []
leftover = mid
curr_day = 1
i = 0
curr_day_schedule = []
while i < len(requests_here):
if curr_day < requests_here[i][0]:
curr_day += 1
continue
if curr_day - requests_here[i][0] > d:
return False
if leftover >= len(requests_here[i][1]):
curr_day_schedule.extend(requests_here[i][1][:])
leftover -= len(requests_here[i][1])
requests_here[i][1].clear()
else:
for _ in range(leftover):
curr_day_schedule.append(requests_here[i][1].pop())
schedule.append(curr_day_schedule)
curr_day_schedule = []
leftover = mid
curr_day += 1
i -= 1
i += 1
if curr_day_schedule:
schedule.append(curr_day_schedule)
return schedule
# O(log M * (N + M))
def bs(lo, hi):
hi += 1
while lo < hi:
mid = (lo + hi) // 2
if ok(mid):
hi = mid
else:
lo = mid + 1
return lo, ok(lo)
ans_len, ans = bs(1, m)
print(ans_len)
for i in range(n):
if i >= len(ans):
print(0)
else:
ans[i].append(0)
print(' '.join(map(str, ans[i])))
