Leetcode Minimum path sum

Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.

Note: You can only move either down or right at any point in time.

public class Solution {
    public int minPathSum(int[][] grid) {

        if(grid==null || grid.length== || grid[].length==)return ;
        int dp[][]=new int[grid.length][grid[].length];
        dp[][]=grid[][];
        for(int i=;i<grid.length;i++)dp[i][]=dp[i-][]+grid[i][];
        for(int j=;j<grid[].length;j++)dp[][j]=dp[][j-]+grid[][j];
        for(int i=;i<grid.length;i++)
        {
            for(int j=;j<grid[].length;j++)
            {
                dp[i][j]=Math.min(dp[i-][j], dp[i][j-])+grid[i][j];
            }
        }
        return dp[dp.length-][dp[].length-];
    }
}