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.
import sys
def get_ints(): return list(map(int, sys.stdin.readline().strip().split()))
 
arr = get_ints()
r = arr[0]
c = arr[1]
k = arr[2]
ans = []
if r == k :
    for i in range(1, r + 1):
        ans = []
        ans.append(str(c))
        for j in range(1, k + 1):
            ans.append(str(i) + " " + str(j))
        print(" ".join(ans))
elif c == k :
    for i in range(1, c + 1):
        ans = []
        ans.append(str(r))
        for j in range(1, r + 1):
            ans.append(str(j) + " " + str(i))
        print(" ".join(ans))
elif r > k :
    diff = r - k 
    flip = 0 
    ans = []
    ans.append(str( (diff + 1) * c ) )
    for i in range(1, 1+ diff + 1):
        if flip == 0 :
            for j in range(1, c + 1):
                ans.append(str(i) + " " + str(j))
            flip = 1 
        else:
            for j in range(c, 0, -1):
                ans.append(str(i) + " " + str(j))
            flip = 0
    
    print(" ".join(ans))

    for i in range(k - 1 ):
        i += diff 
        i += 2 
        ans = []
        ans.append(str(c))
        for j in range(1, c + 1):
            ans.append(str(i) + " " + str(j))
        print(" ".join(ans)) 
else:
    diff = c - k 
    flip = 0 
    ans = []
    ans.append(str( (diff + 1) * r ) )
    for i in range(1, 1+ diff + 1):
        if flip == 0 :
            for j in range(1, r + 1):
                ans.append(str(j) + " " + str(i))
            flip = 1 
        else:
            for j in range(r, 0, -1):
                ans.append(str(j) + " " + str(i))
            flip = 0
    
    print(" ".join(ans))

    for i in range(k - 1 ):
        i += diff 
        i += 2 
        ans = []
        ans.append(str(r))
        for j in range(1, r + 1):
            ans.append(str(j) + " " + str(i))
        print(" ".join(ans)) 
    
