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.
# 441C

__author__ = 'artyom'

n, m, k = map(int, input().split())
i, j, d, t = 1, 1, 1, 1
ans = ''


def get_next(x, y, dir):
  y += dir
  if y > m:
    y = m
    x += 1
    dir = -1
  if y == 0:
    y = 1
    x += 1
    dir = 1
  return x, y, dir


while t < k:
  ans += '2 ' + str(i) + ' ' + str(j)
  i, j, d = get_next(i, j, d)
  ans += ' ' + str(i) + ' ' + str(j) + '\n'
  i, j, d = get_next(i, j, d)
  t += 1
rem = n * m - (t - 1) * 2
ans += str(rem)
while rem > 0:
  ans += ' ' + str(i) + ' ' + str(j)
  i, j, d = get_next(i, j, d)
  rem -= 1

print(ans)