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.
#Inicio de programa
row,column,tubes = input().split(" ")
row = int(row)
column = int(column)
tube = int(tubes)
flag = bool(1)
k = int(1)
x = int(1)
#print(lines,row,column,tubes,result)

res = int(row*column/tube); #int si no no me dejara en el ciclo recorrer
if (res < 2):
	res = int(2)

for i in range(1,tube,1):
	#print("Estoy dentro for 1")
	print(res, "",end='')
	for j in range(1,res,1):
			#print("Estoy dentro for 2.2")
		if (k >= 1 and k <= column): 
			#print("Opt 1")
			print(x,k,"",end='')
			k = k + flag
		if (k > column):
			#print("Opt 2")
			k = column
			x = x + 1
			flag = -1
		if (k < 1):
			#print("Opt 3")
			k = 1
			x = x + 1
			flag = 1
	print ("")
res = row*column-(tube-1)*res
print(res,"",end='')

for i in range (1,res,1):
	#print("Estoy dentro for 2.1")
	if (k >= 1 and k <= column):
		print(x,k,"",end='')
		k = k + flag
	if (k > column):
		k = column
		x = x + 1
		flag = -1
	if (k < 1):
		k = 1
		x = x + 1
		flag = 1
print ("")

#End of the program
	    		 	  	  	  			 	   					