Valera has got a rectangle table consisting of *n* rows and *m* columns. Valera numbered the table rows starting from one, from top to bottom and the columns – starting from one, from left to right. We will represent cell that is on the intersection of row *x* and column *y* by a pair of integers (*x*, *y*).

Valera wants to place exactly *k* tubes on his rectangle table. A tube is such sequence of table cells (*x*<sub class="lower-index">1</sub>, *y*<sub class="lower-index">1</sub>), (*x*<sub class="lower-index">2</sub>, *y*<sub class="lower-index">2</sub>), ..., (*x*<sub class="lower-index">*r*</sub>, *y*<sub class="lower-index">*r*</sub>), that: 
 -  *r* ≥ 2; -  for any integer *i* (1 ≤ *i* ≤ *r* - 1) the following equation |*x*<sub class="lower-index">*i*</sub> - *x*<sub class="lower-index">*i* + 1</sub>| + |*y*<sub class="lower-index">*i*</sub> - *y*<sub class="lower-index">*i* + 1</sub>| = 1 holds; -  each table cell, which belongs to the tube, must occur exactly once in the sequence. 
Valera thinks that the tubes are arranged in a fancy manner if the following conditions are fulfilled: 
 -  no pair of tubes has common cells; -  each cell of the table belongs to some tube. 
Help Valera to arrange *k* tubes on his rectangle table in a fancy manner.
The first line contains three space-separated integers *n*, *m*, *k* (2 ≤ *n*, *m* ≤ 300; 2 ≤ 2*k* ≤ *n*·*m*) — the number of rows, the number of columns and the number of tubes, correspondingly.
def zip_sorted(a,b):

	# sorted  by a
	a,b = zip(*sorted(zip(a,b)))
	# sorted by b
	sorted(zip(a, b), key=lambda x: x[1])

	return a,b

import sys
input = sys.stdin.readline
I = lambda : list(map(int,input().split()))
S = lambda : list(map(str,input().split()))


n,m,k = I()
dp = [[0 for i in range(m)] for j in range(n)]
if m%2==0:
	s1 = True
else:
	s1 = False
s2 = [[] for i in range(k)]
for l in range(k):
	if l!=k-1:
		count= 0 
		for i in range(len(dp)):
			if i%2==0:
				for j in range(len(dp[i])):
					if dp[i][j]==1:
						continue
					if count==2:
						break
					s2[l].append(i+1)
					s2[l].append(j+1)
					dp[i][j]=1
					count+=1				
			else:
				for j in range(len(dp[i])-1,-1,-1):
					if dp[i][j]==1:
						continue
					if count==2:
						break
					s2[l].append(i+1)
					s2[l].append(j+1)
					dp[i][j]=1
					count+=1
			if count==2:
				break
	else:
		for i in range(len(dp)):
			if i%2==0:
				for j in range(len(dp[i])):
					if dp[i][j]==1:
						continue
					s2[l].append(i+1)
					s2[l].append(j+1)
					dp[i][j]=1
			else:
				for j in range(len(dp[i])-1,-1,-1):
					if dp[i][j]==1:
						continue
					s2[l].append(i+1)
					s2[l].append(j+1)
					dp[i][j]=1
for i in range(len(s2)):
	print(int(len(s2[i])/2),end=' ')
	print(*s2[i])
