#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define each(a,b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end())
#define fi first
#define se second
#define pb push_back
#define show(x) cout<<#x<<" = "<<(x)<<endl
#define spair(p) cout<<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout<<" "<<kbrni;cout<<endl
#define smap(m) cout<<#m<<":";each(kbrni,m)cout<<" {"<<kbrni.first<<":"<<kbrni.second<<"}";cout<<endl

using namespace std;

typedef pair<int,int>P;

const int MAX_N = 100;

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

struct state
{
    int px,py,nx,ny,dir;
};

int val[MAX_N][MAX_N];

bool possible(int a,int b,int c,int d,int e,int f)
{
    if(a < 0){
        return true;
    }
    if(val[a][b] == val[c][d] || val[a][b] == val[e][f] || val[c][d] == val[e][f]){
        return false;
    }
    if(val[a][b] > val[c][d]){
        if(val[c][d] > val[e][f]){
            return false;
        }else{
            return true;
        }
    }else{
        if(val[c][d] < val[e][f]){
            return false;
        }else{
            return true;
        }
    }
}

int d[MAX_N][MAX_N][4];

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int w,h;
    cin >> w >> h;
    rep(i,h){
        rep(j,w){
            cin >> val[i][j];
        }
    }
    rep(i,h){
        rep(j,w){
            rep(k,4){
                d[i][j][k] = INF;
            }
        }
    }
    queue<state> que;
    que.push((state){-1,-1,0,0,0});
    rep(i,4){
        d[0][0][i] = 0;
    }
    while(!que.empty()){
        state s = que.front();
        que.pop();
        rep(i,4){
            int u = s.nx+dx[i],v = s.ny+dy[i];
            if(0 <= u && u < h && 0 <= v && v < w && d[u][v][i] > s.dir + 1 && possible(s.px,s.py,s.nx,s.ny,u,v)){
                d[u][v][i] = s.dir + 1;
                que.push((state){s.nx,s.ny,u,v,s.dir+1});
            }
        }
    }
    int ans = INF;
    rep(i,4){
        ans = min(ans,d[h-1][w-1][i]);
    }
    if(ans == INF){
        cout << "-1\n";
    }else{
        cout << ans << endl;
    }
    return 0;
}