Question

我需要维数组的总和.......... 如何添加二维数组的总和，我完成了这个，但当我尝试添加标记[i] [j]时，我无法实现...

import java.util.Scanner;
public class TwoDimArray {
    static int i, j;
    public static void main(String[ ] args) {
        int [ ][ ] marks = new int [4][4];
        Scanner sc = new Scanner(System.in);
        for (i = 1; i < marks.length ; i ++) {
            System.out.println ("Enter marks of student "+i);
            for ( j = 1; j < marks[i].length ; j++) {
                System.out.println ("Subject "+j);
                marks [i][j] = sc.nextInt();
            }
        } 
        for ( i = 1; i < marks.length ; i++) {
            for ( j = 1; j < marks[i].length ; j++){
                System.out.print (marks[i][j]+" ");

            }
        }
    }
}

output:
Enter marks of student 1
Subject 1
45
Subject 2
48
Subject 3
47
Enter marks of student 2
Subject 1
52
Subject 2
56
Subject 3
54
Enter marks of student 3
Subject 1
65
Subject 2 
66
Subject 3
75

45 48 47 52 56 54 65 66 75 
*/

我想要总和[i] [j]，我怎么能加上它的总和科目，请解释科目总结...

Answer 1

非常简单。首先是一些评论：

static int i, j;不知道你为什么要这样做。只需在for-loop中声明它们。
由于除了选择正确的标记之外，您不对i和j执行任何操作，请使用foreach循环：for (int[] marksFromStudent : marks) {...
第一个数组索引是0，而不是1.

现在代码。我添加了一些代码来显示学生总数：

int[][] marks = getMarksFromScanner(); //the question is not about this part; might as well omit it.
int total = 0;
for (int i = 0; i < marks.length; i++) {
    int studentTotal = 0;
    for (int mark : marks[i]) 
        studentTotal += mark;
    System.out.println("student " + i + " has a total of " + studentTotal + " points");
    total += studentTotal;
}
System.out.println("The whole class scored " + total + " points");

或没有学生总和的简单版本：

int[][] marks = getMarksFromScanner(); //the question is not about this part; might as well omit it.
int total = 0;
for (int[] studentMarks : marks)
    for (int mark : studentMarks)
        total += mark;
System.out.println(total);

如何添加二维数组，这个程序

1 个答案: