def f(ar, x, n, d, m):
st = []
new_req = 0
for i in range(1, n + 1):
st.append([])
for j in range(x):
if ar[new_req][0] > i:
break
if new_req + d >= i:
#st += str(ar[new_req][1]) + ' '
st[i-1].append(ar[new_req][1])
new_req += 1
else:
return False, st
if new_req == m:
return True, st
return False, st
def lower_bound(ar):
global stor1
l = 0
r = len(ar)
while r - l != 1:
mid = (r + l) // 2
stor = f(ar, mid, n, d, m)
if stor[0]:
r = mid
stor1 = stor
else:
l = mid
return r
stor1 =''
n, d, m = map(int, input().split())
ar = list(map(int, input().split()))
for i in range(m):
ar[i] = [ar[i], i + 1]
ar.sort()
print(lower_bound(ar))
#print(stor1[1])
for i in range(n):
if i >= len(stor1[1]):
print('0')
elif stor1[1][i] == []:
print('0')
else:
print(" ".join(map(str, stor1[1][i])) + ' 0')
