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

    l = n * m // k  # Lenght of each tube
    lf = n * m - (l * (k - 1))  # Lenght of the first tube

    # print(f"First Tube Length: {lf}")
    # print(f"Next Tubes Length: {l}")
    # print(f"Total Number of Tubes: {k}")

    direction = 1  # 1 means moving right; -1 means moving left;

    position = [1, 1]
    ti = 0  # tube index
    tube = []
    sizes = [lf]
    for _ in range(k - 1):
        sizes.append(l)

    filled_cells = 0

    while filled_cells < n * m:
        tube.append(list(position))
        filled_cells += 1

        if len(tube) == sizes[ti]:
            print(f"{len(tube)} {' '.join(f'{t[0]} {t[1]}' for t in tube)}")
            tube = []
            ti += 1

        position[1] += direction

        if position[1] > m:
            position[1] = m
            position[0] += 1
            direction = -1

        if position[1] < 1:
            position[1] = 1
            position[0] += 1
            direction = 1


solve()
