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()) 
ans=[]
curr=1 #fwd 
now=[1,1]
tr=[]
tr.append(now)
z=n*m
while z : 
    z-=1 
    x=now[0]
    y=now[1]
    if curr==1:
        if y+1>m:
            #y-=1 
            x+=1 
            curr=-1 
        else: 
            x+=0 
            y+=1 
        #curr=-1 
        now=[x,y]
    else:
        if y==1: 
          #  y-=1 
            x+=1 
            curr=1 
        else:
            x+=0 
            y-=1 
        now=[x,y]
    tr.append(now)
le=n*m 
j=0 
ans=tr[:]
sm=0 
while k>1: 
    print(2,ans[j][0],ans[j][1],ans[j+1][0],ans[j+1][1])
    k-=1  
    j+=2 
    sm+=2 
rem=n*m-sm 
print(rem,end=' ')
for k in range(j,n*m):
    print(ans[k][0],ans[k][1],end=' ')
