#include <fstream>

using namespace std;
ifstream f("elimin.in");
ofstream g("elimin.out");
int main()
{
   int M,N,R,C,a[100][100],z=0,x,y,i,j,s=0,s1=0,su=0,su1=0,suc=0,sul=0,ok=0,nrc=0,nrl=0;
   f>>M>>N>>R>>C;
   for(i=1;i<=M;i++)
        for(j=1;j<=N;j++)
            f>>a[i][j];

   while(ok!=N)
        {   ok++;
            for(j=1;j<=N;j++)
                if(ok%2==0)
                    {s1=s1+a[j][ok];
                    x=ok;}
                else
                    {s=s+a[j][ok];
                    y=ok;}
            if(s<s1)
                {suc=s;
                nrc=ok;}
            else
                {suc=s1;
                nrc=ok;}
                if(x==y+1)
                    s=0;
                if(y==x+1)
                    s1=0;
        }
    ok=0;

 while(ok!=M)
        {   ok++;
            for(i=1;i<=M;i++)
                if(ok%2==0)
                    {su1=su1+a[i][ok];
                    x=ok;}
                else
                    {su=su+a[i][ok];
                    y=ok;}
            if(su<su1)
                {sul=su;
                nrl=ok;}
            else
                {sul=su1;
                nrl=ok;}
            if(x==y+1)
                    su=0;
                if(y==x+1)
                    su1=0;
        }
         for(i=1;i<=M;i++)
            if(nrl==i)
                for(j=1;j<=N;j++)
                        a[i][j]=0;
        for(i=1;i<=M;i++)
                for(j=1;j<=N;j++)
                    if(nrc==j)
                        a[i][j]=0;

    for(i=1;i<=M;i++)
        for(j=1;j<=N;j++)
            z=z+a[i][j];
    g<<z;
    return 0;
}