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 ValeraAndTubes(n,m,k):
	minCellsPerTube = (n*m)//k
	l=((n*m)%k)+minCellsPerTube
	reqLength = minCellsPerTube

	i=1
	j=1

	result=str(reqLength)+" "
	
	while i<=n:
		if j>m:
			j=m
		elif j==0:
			j=1
		if(i%2!=0):
			while j<=m:	
				reqLength-=1						
				result+=str(i)+" "+str(j)+" "	
				if(reqLength==0):
					print(result)
					k-=1
					if k==1:
						reqLength = l
					else:
						reqLength = minCellsPerTube
					result=str(reqLength)+" "		
				j+=1
		else:
			while j>0 and k>0:
				reqLength-=1						
				result+=str(i)+" "+str(j)+" "
				if(reqLength==0):
					print(result)
					k-=1
					if k==1:
						reqLength = l
					else:
						reqLength = minCellsPerTube
					result=str(reqLength)+" "	
				j-=1
		i+=1


n,m,k = [int(x) for x in input().split()]
ValeraAndTubes(n,m,k)