CCsky

#include <fstream>
#include <cmath>
#include <deque>
using namespace std;

ifstream cin("ccski.in");
ofstream cout("ccski.out");

#define INF 2000000001
#define N_MAX 501


int ml[]={1,0,-1,0};
int mc[]={0,1,0,-1};

int lee[N_MAX][N_MAX],v[N_MAX][N_MAX];
bool mat[N_MAX][N_MAX];

int main()
{
    int n,m,i,j,l,c,cntd,cntc,max1,cs;
    cin>>n>>m;
    deque<pair<int,int>> mers;
    deque<int> cnt;
    for(i=1;i<=n;i++){
        for(j=1;j<=m;j++){
            cin>>v[i][j];
            lee[i][j]=INF;
        }
    }
    for(i=1;i<=n;i++){
        for(j=1;j<=m;j++){
            cin>>mat[i][j];
            if(mat[i][j]==1){
                cs++;
                mers.push_back({i,j});
                cnt.push_back(0);
            }
        }
    }
    while(!mers.empty()){
        cntd=cnt.front();
        pair <int,int> poz;
        poz=mers.front();
        mers.pop_front();
        cnt.pop_front();
        for(i=0;i<4;i++){
            l=poz.first+ml[i];
            c=poz.second+mc[i];
            if(l>0 && c>0 && l<=n && c<=m){
                cntc=max(cntd,abs(v[l][c]-v[poz.first][poz.second]));
                if(cntc<lee[l][c] && lee[l][c]<INF){
                    lee[l][c]=cntc;
                    mers.push_front({l,c});
                    cnt.push_front(cntc);
                }else if(cntc<lee[l][c]){
                    lee[l][c]=cntc;
                    mers.push_back({l,c});
                    cnt.push_back(cntc);
                }
            }
        }
    }
    max1=0;
    for(i=1;i<=n;i++){
        for(j=1;j<=m;j++){
            if(mat[i][j]==1 && lee[i][j]>max1){
                max1=lee[i][j];
            }
        }
    }
    if(cs==1)
        cout<<"0";
    else
        cout<<max1;
    return 0;
}