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 generateNext(i,j,c):
    if i%2==1:
        if j==c:
            return [i+1,j]
        else:
            return [i,j+1]
    else:
        if j==1:
            return [i+1,j]
        else:
            return [i,j-1]



def main():
    r,c,k = list(map(int,input().split()))
    left = r*c
    i=1
    j=1
    while k>0:
        if k!=1:
            print(2,end=" ")
            print(i, j, end=" ")
            i,j = generateNext(i,j,c)
            print(i, j, end=" ")
            i,j = generateNext(i,j,c)
            left=left-2
        else:
            print(left,end=" ")
            while left>0:
                print(i, j, end=" ")
                i,j = generateNext(i,j,c)
                left = left-1
        print("")
        k=k-1

main()