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.

if __name__ == '__main__':
    n, m, k = [int(x) for x in input().split()];
    cells = n * m
    direction, x, y = 1, 1, 1
    for i in range(k - 1):
        s = "2 "

        for j in range(2):
            s += str(x) + " " + str(y)
            y += direction
            cells -= 1
            if (j == 0):
                s += " "
            if (not (y <= m and y > 0)):
                direction = 1 if direction == -1 else -1
                y += direction
                x += 1

        print(s)

    s = str(cells) + " "
    while (cells > 0):
        s += str(x) + " " + str(y)
        y += direction
        cells -= 1
        if (cells > 0):
            s += " "
        if (not (y <= m and y > 0)):
            direction = 1 if direction == -1 else -1
            y += direction
            x += 1
    print(s)