from sys import stdin
pin=stdin.readline
H,W,N=map(int,pin().split())
C=[list(map(int,pin().split()))for _ in[0]*H]
d=[[]for _ in[0]*N]
for i in range(H):
 for j in range(W):
  d[C[i][j]-1].append((i,j))
a=s=1
for i in range(N):
 f=0
 for x,y in d[i]:
  for u,t in ((1,0),(0,1),(-1,0),(0,-1)):
   if 0<=x+u<H and 0<=y+t<W and s<=C[x+u][y+t]<C[x][y]:
    a+=1;f=1;s=C[x][y]
    break
  if f:break
print(a)