#!/usr/local/bin/tcc -run
#include<stdio.h>

int main(void){
    int N,M,D,i,j,k,count=0,keep,ix,iy,ans=0;
    int map[1002][1002];
    int result[1000*1000+1];
    int x[1000*1000+1];
    int y [1000*1000+1];

    scanf("%d%d%d",&N,&M,&D);
    for(i=0;i<=M+2;i++){
       map[0][i]=10000000;
       map[N+2][i]=10000000; 
    } 
    for(i=1;i<=N;i++){
        map[i][0]=10000000;
        map[i][M+1]=10000000;
    }
    for(i=1;i<=N;i++){
        for(j=1;j<=M;j++){
            scanf("%d",&k);
            x[k]=i;
            y[k]=j;
        }
    }

    for(i=1;i<=N*M;i++){
        ix=x[i];
        iy=y[i];
        if(map[ix-1][iy]<i){
            keep=result[map[ix-1][iy]];
            count++;
            if(result[map[ix-1][iy]]==-1){
                result[i]=-1;
                keep=0;
                ans++;
                continue;
            }
        }
        if(map[ix+1][iy]<i){
            if(result[map[ix+1][iy]]==-1){
                result[i]=-1;
                keep=0;
                ans++;
                continue;
            }
            if(keep!=result[map[ix+1][iy]]){
                result[i]=-1;
                ans++;
                continue;
            }
        }
        if(map[ix][iy-1]<i){
            if(result[map[ix][iy-1]]==-1){
                result[i]=-1;
                keep=0;
                ans++;
                continue;
            }
            if(keep!=result[map[ix][iy-1]]){
                result[i]=-1;
                ans++;
                continue;
            }
        }
        if(map[ix][iy+1]<i){
            if(result[map[ix][iy+1]]==-1){
                result[i]=-1;
                keep=0;
                ans++;
                continue;
            }
            if(keep!=result[map[ix][iy+1]]) {
                result[i]=-1;
                ans++;
                continue;
            }
        }
        if(keep==0) result[i]=i;
        if(keep!=0) result[i]=keep;
        count=0;
        keep=0;
    }
    printf("%d",ans);
    return 0;
}