import java.util.Scanner;


public class Podtablice {
	public static Scanner inScan = new Scanner(System.in);
	public static int tab[][];

	public static void makeTab(){
		int n=inScan.nextInt();
		int m=inScan.nextInt();

		tab=new int[n][m];
		for(int i=0;i<n;i++){
			for(int j=0;j<m;j++){
				tab[i][j]=inScan.nextInt(); //moja podtablica
			}
		}
	}

	public static int tabGreatestSum() {
            int max=0;
            int temp;
		for(int j=0;j<tab.length;j++){
			for(int i=0;i<=j;i++){
				for(int l=0;l<tab[0].length;l++){
					for(int k=0;k<=l;k++){
						temp=s(i,j,k,l);
                                                if(temp>max){
							max=temp;
						}

						//System.out.println(i+""+j+""+k+""+l+""+temp);
					}
				}
			}
		}
		return max;
	}


	private static int s(int i, int j, int k, int l) {
		// TODO Auto-generated method stub
		int temp=0;
		//System.out.println(i+""+j+""+k+""+l+""+temp);
		while(i<=j){
			int kk=k;
			while(kk<=l){
				temp+=tab[i][kk];
				kk++;
			}
			i++;
		}

		//System.out.println(i+""+j+""+k+""+l+"");

		return temp;
	}