#include <bits/stdc++.h>
using namespace std;
const int INF=2e9;
int n;

struct node{
    int vi,vj,w;
    bool operator < (const node & rhs) const{
        return  ! (w< rhs.w) ;
    }
};
int main(){

    scanf("%d",&n);
    int si=-1,sj=-1,mx=0,ei=-1,ej=-1;
    vector <int> ar[n+5];
    vector <long long> dis[n+5];
    vector <bool> visited[n+5];
    vector <node> g[n+5][n+5];
    for(int i=1;i<=n;i++){
        ar[i].push_back(0);
        visited[i].push_back(0);
        dis[i].push_back(INF);
        for(int j=1;j<=n;j++){
            dis[i].push_back(INF);
            visited[i].push_back(0);
            int x;
            scanf("%d",&x);
            ar[i].push_back(x);
            if(ar[i][j]==0){
                if(si==-1 && sj==-1){
                    si=i;
                    sj=j;
                }
                else {
                    ei=i;
                    ej=j;
                }
            }

            if(i>1){
                g[i][j].push_back({i-1,j,ar[i-1][j]});
                g[i-1][j].push_back({i,j,ar[i][j]});
            }
            if(j>1){
                g[i][j].push_back({ i,j-1,ar[i][j-1] });
                g[i][j-1].push_back({ i,j,ar[i][j] });
            }
        }
    }

    priority_queue < node > pq;

    dis[si][sj]=0;
    pq.push({ si,sj,dis[si][sj] });


    while(pq.size()>0){
        int ui=pq.top().vi , uj=pq.top().vj , d=pq.top().w;
        pq.pop();

        if (visited[ui][uj])
            continue;
        visited[ui][uj]=true;

        if(ar[ui][uj]>mx) mx=ar[ui][uj];

        if( ei==ui && ej==uj ) {
            printf("%d ",mx);
            break;
        }

        if(ar[ui][uj]>mx) mx=ar[ui][uj];

        for(auto vw:g[ui][uj]){
            int vi,vj,w;
            vi=vw.vi;
            vj=vw.vj;
            w=vw.w;
            if(visited[vi][vj]==false && dis[ui][uj]+w<dis[vi][vj] ){
                dis[vi][vj] = dis[ui][uj] + w;
                pq.push({ vi,vj,ar[vi][vj]});
            }
        }

    }


    return 0;
}