//#include<bits/stdc++.h>

#include<iostream>

#include<cstdio>

#include<ctime>

#include<cctype>

#include<queue>

#include<deque>

#include<stack>

#include<iostream>

#include<iomanip>

#include<cstdio>

#include<cstring>

#include<string>

#include<ctime>

#include<cmath>

#include<cctype>

#include<cstdlib>

#include<queue>

#include<deque>

#include<stack>

#include<vector>

#include<algorithm>

#include<utility>

#include<bitset>

#include<set>

#include<map>

#define ll long long

#define db double

#define INF 1000000000

#define inf 100000000000000000ll

#define ldb long double

#define pb push_back

#define put_(x) printf("%d ",x);

#define get(x) x=read()

#define gt(x) scanf("%d",&x)

#define gi(x) scanf("%lf",&x)

#define put(x) printf("%d\n",x)

#define putl(x) printf("%lld\n",x)

#define rep(p,n,i) for(RE int i=p;i<=n;++i)

#define go(x) for(int i=lin[x],tn=ver[i];i;tn=ver[i=nex[i]])

#define fep(n,p,i) for(RE int i=n;i>=p;--i)

#define vep(p,n,i) for(RE int i=p;i<n;++i)

#define pii pair<int,int>

#define mk make_pair

#define RE register

#define P 1000000007ll

#define gf(x) scanf("%lf",&x)

#define pf(x) ((x)*(x))

#define uint unsigned long long

#define ui unsigned

#define EPS 1e-10

#define sq sqrt

#define S second

#define F first

#define mod 1000000007

#define id(i,j) ((i-1)*m+j)

#define max(x,y) ((x)<(y)?y:x)

using namespace std;

char *fs,*ft,buf[1<<15];

inline char gc()

{

	return (fs==ft&&(ft=(fs=buf)+fread(buf,1,1<<15,stdin),fs==ft))?0:*fs++;

}

inline int read()

{

	RE int x=0,f=1;RE char ch=gc();

	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=gc();}

	while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=gc();}

	return x*f;

}

const int MAXN=510,maxn=MAXN*MAXN;

int n,m,top,rt,k,len,num;

int a[maxn],f[MAXN],son[MAXN],sz[MAXN];

ll c[MAXN],mx[MAXN],ans,cnt;

int lin[maxn],ver[maxn],nex[maxn];

inline void add(int x,int y)

{

	ver[++len]=y;

	nex[len]=lin[x];

	lin[x]=len;

}

priority_queue<ll>q;

inline int getfather(int x){return x==f[x]?x:f[x]=getfather(f[x]);}

struct wy

{

	int x,y;

	int z;

	inline bool operator <(wy a)const{return z<a.z;}

}t[maxn];

int dx[4]={0,0,1,-1};

int dy[4]={1,-1,0,0};

inline void dfs(int x)

{

	sz[x]=1;

	go(x)

	{

		dfs(tn);

		c[tn]=(ll)(a[x]-a[tn])*sz[tn];

		ans+=c[tn];mx[tn]+=c[tn];

		if(mx[tn]>mx[x])

		{

			mx[x]=mx[tn];

			son[x]=tn;

		}

		sz[x]+=sz[tn];

	}

}

inline void dp(int x,int fa)

{

	if(x==fa)q.push(mx[x]);

	if(son[x])dp(son[x],fa);

	go(x)if(tn!=son[x])dp(tn,tn);

}

int main()

{

	//freopen("1.in","r",stdin);

	get(n);get(m);get(k);

	rep(1,n,i)rep(1,m,j)

	{

		int get(x);

		f[id(i,j)]=id(i,j);

		t[++num]=(wy){i,j,x};

	}

	//cout<<id(1,2)<<endl;

	sort(t+1,t+1+num);

	//cout<<t[1].z<<endl;

	rep(1,num,i)

	{

		int x=t[i].x;

		int y=t[i].y;

		int id=id(x,y);

		rep(0,3,k)

		{

			int xx=dx[k]+x;

			int yy=dy[k]+y;

			if(xx<1||yy<1||xx>n||yy>m)continue;

			if(!a[id(xx,yy)])continue;

			int w1=getfather(id(xx,yy));

			if(w1==id)continue;

			f[w1]=id;add(id,w1);

		}

		a[id]=t[i].z;

	}

	rt=id(t[num].x,t[num].y);

	//put(rt);

	//cout<<getfather(1)<<endl;

	dfs(rt);dp(rt,rt);

	while(q.size()&&k)

	{

		ans-=q.top();

		cnt=cnt^ans;

		q.pop();--k;

	}

	putl(cnt);

	return 0;

}