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.
n, m, k = map(int, input().split())

size = (n * m) // k 

temp = []
tubes = []
count = 0
flag = True
for i in range(n):
    if flag:
        for j in range(m):
            temp.append((i + 1, j + 1))
            count += 1 
            if count == size and len(tubes) < k - 1:
                tubes.append(temp)
                count = 0
                temp = []
        flag = False
    else:
        for j in reversed(range(m)):
            temp.append((i + 1, j + 1))
            count += 1 
            if count == size and len(tubes) < k - 1:
                tubes.append(temp)
                count = 0
                temp = []
        flag = True
if temp:
    tubes.append(temp)
for t in tubes:
    s = str(len(t)) + ' '
    for p in t:
        s += str(p[0]) + ' ' + str(p[1]) + ' '
    print(s)