#include<iostream>

#include<cstdio>

#include<cmath>

#include<cstdlib>

#include<cstring>

#include<algorithm>

using namespace std;

#define ll long long

#define N 10010

#define K 2010

#define S 10001

#define T 10002

char getc(){char c=getchar();while ((c<'A'||c>'Z')&&(c<'a'||c>'z')&&(c<''||c>'')) c=getchar();return c;}

int gcd(int n,int m){return m==?n:gcd(m,n%m);}

int read()

{

    int x=,f=;char c=getchar();

    while (c<''||c>'') {if (c=='-') f=-;c=getchar();}

    while (c>=''&&c<='') x=(x<<)+(x<<)+(c^),c=getchar();

    return x*f;

}

int n,m,id[K][],p[N],d[N],q[N],pre[N],t=-,cnt,tot,ans,val;

bool flag[N];

struct data{int to,nxt,cap,flow,cost;

}edge[N<<];

void addedge(int x,int y,int z,int cost)

{

    t++;edge[t].to=y,edge[t].nxt=p[x],edge[t].cap=z,edge[t].flow=,edge[t].cost=cost,p[x]=t;

    t++;edge[t].to=x,edge[t].nxt=p[y],edge[t].cap=,edge[t].flow=,edge[t].cost=-cost,p[y]=t;

}

inline int trans(int x,int y){return (x-)*m+y;}

inline bool isblack(int x,int y){return (x&)^(y&);}

inline int inc(int &x){x++;if (x>cnt+) x-=cnt+;return x;}

bool spfa()

{

    memset(d,,sizeof(d));d[S]=;

    memset(flag,,sizeof(flag));

    int head=,tail=;q[]=S;

    do

    {

        int x=q[inc(head)];flag[x]=;

        for (int i=p[x];~i;i=edge[i].nxt)

        if (d[x]+edge[i].cost<d[edge[i].to]&&edge[i].flow<edge[i].cap)

        {

            d[edge[i].to]=d[x]+edge[i].cost;

            pre[edge[i].to]=i;

            if (!flag[edge[i].to]) q[inc(tail)]=edge[i].to,flag[edge[i].to]=;

        }

    }while (head!=tail);

    return d[T]<N;

}

void ekspfa()

{

    while (spfa())

    {

        int v=;

        for (int i=T;i!=S;i=edge[pre[i]^].to)

        if (edge[pre[i]].cap==edge[pre[i]].flow) {v=;break;}

        if (v)

        {

            ans++;

            for (int i=T;i!=S;i=edge[pre[i]^].to)

            val+=edge[pre[i]].cost,edge[pre[i]].flow++,edge[pre[i]^].flow--;

        }

    }

}

int main()

{

#ifndef ONLINE_JUDGE

    freopen("bzoj5120.in","r",stdin);

    freopen("bzoj5120.out","w",stdout);

    const char LL[]="%I64d\n";

#else

    const char LL[]="%lld\n";

#endif

    n=read(),m=read();

    memset(p,,sizeof(p));

    for (int i=;i<=n;i++)

        for (int j=;j<=m;j++)

        {

            int x=read(),u=,v=trans(i,j);

            for (int k=;k<;k++)

            {

                id[v][k]=++cnt;

                if (x&(<<k)) u++,isblack(i,j)?addedge(S,cnt,,):addedge(cnt,T,,);

            }

            tot+=u;

            if (x==||x==) continue;

            if (u==||u==) for (int k=;k<;k++) addedge(id[v][k],id[v][k+&],,),addedge(id[v][k+&],id[v][k],,);

            if (u==)

            {

                addedge(id[v][],id[v][],,),addedge(id[v][],id[v][],,);

                addedge(id[v][],id[v][],,),addedge(id[v][],id[v][],,);

            }

        }

    if (tot&) {cout<<-;return ;}tot>>=;

    for (int i=;i<=n;i++)

        for (int j=;j<=m;j++)

        if (isblack(i,j))

        {

            int v=trans(i,j);

            if (i>) addedge(id[v][],id[trans(i-,j)][],,);

            if (j<m) addedge(id[v][],id[trans(i,j+)][],,);

            if (i<n) addedge(id[v][],id[trans(i+,j)][],,);

            if (j>) addedge(id[v][],id[trans(i,j-)][],,);

        }

    ekspfa();

    if (ans<tot) cout<<-;

    else cout<<val;

    return ;

}