试图找到最后一列的总和

Question

public class arsum
{

 static int[][] myarray = {{1, 2, 3, 4}, {5, 6, 7, 8}, {1, 2, 3, 4}};

 public int[] summing(int[][] array)

 {
    int index = 0;
    int a[] = new int[array[index].length];
    for (int i = 0; i < array[0].length; i++)
    {
        int sum = 0;
        for (int j = 0; j < array.length; j++)
        {
            sum += array[j][i]; 
        }
        a[index] = sum;
        System.out.println(sum);
    }
    return a;
 } 

 public static void main(String[] args) {
    new arsum().summing(myarray);
 }

}

目前它打印出所有4列的总和，但我只想要最后一笔。我无法弄清楚如何为任何通用数组正确编码。

我是编码的新手，还没有完全弄明白。

Answer 1

尝试，

  int[][] myarray = {{1, 2, 3, 4}, {5, 6, 7, 8}, {1, 2, 3, 4}};
  int sum = 0;
  for (int nums[] : myarray) {
        sum += nums[nums.length - 1];
  }
  System.out.println(sum);

Answer 2

you can also use array indexing to print sum of last column as below:-

public static int summing(int[][] array)

    {
        int row = array.length;

        int sum = 0;

        for (int i = row - 1; i > row - 2; i--) {
            int col = myarray[i].length;
            for (int j = 0; j < col; j++) {
                sum += array[i][j];

            }

            System.out.println(sum);

        }
        return sum;
    }