package DP;

import java.util.Scanner;

/**
 * @author dx
 * @version 1.0
 * @date 2022年5月16日 19:44
 * @description: 剑指offer 47 礼物的最大价值
 */
public class Maxvalue {

 public static void main(String[] args) {
 Scanner sr = new Scanner(System.in);
 int m = sr.nextInt();
 int n = sr.nextInt();
 int [][]arr = new int[m][n];
 sr.nextLine();//用于跳过行列后的回车符
 for(int i = 0;i < m;i++){
 for(int j = 0;j < n;j++){
 arr[i][j] = sr.nextInt();
 }
 }
 int ans = new Maxvalue_Solution().maxValue(arr);
 System.out.println(ans);
 }
}


class Maxvalue_Solution{


 public int maxValue(int[][] grid) {

 int m = grid.length;
 int n = grid[0].length;
 int [][]dp = new int[m][n];

 dp[0][0] = grid[0][0];

 for(int i = 0;i<m;i++){
 for(int j = 0;j<n;j++){
 if(i == 0 && j == 0) continue;
 else if(i == 0) dp[i][j] = dp[i][j-1]+grid[i][j];
 else if(j == 0) dp[i][j] = dp[i-1][j]+grid[i][j];
 else{
 dp[i][j] = Math.max(dp[i-1][j],dp[i][j-1])+grid[i][j];
 }

 }
 }
 return dp[m-1][n-1];
 }
}