Java错误: illegal start of the expressions

Question

public class Flatten {
    public static int[] flatten(int[][] x) {
        int totalLength = 0;

        for (int i = 0; i < x.length; i++) {
            if (x[i].length > 0) {
                for (int j = 0; j < x[i].length; j++) {
                    totalLength += 1;
                }
            }
        }

        int[] a = new int[totalLength];
        int aIndex = 0;

        for (int i = 0; i < x.length; i++) {
            if (x[i].length > 0) {
                for (int j = 0; j < x[i].length; j++) {
                    a[aIndex] = x[i][j];
                    aIndex += 1;
                }
            }
        }

        return a;
    }

    public static void main(String[] args) {
        int[] test = flatten({{1, 2, 3}, {}, {7, 8}});     // Error line
        for(int i = 0; i < test.length; i++){
            System.out.print(test[i] + " ");
        }
    }
}

大家好!这是我的作业文件中的一个简短代码。当我运行代码时，终端显示“=”是非法的。我不知道问题出在哪里。希望你们能帮我找出答案:)

Answer 1

唯一可以在数组初始值设定项上省略类型的情况是在声明数组变量时。例如，

int[] test = flatten({{1, 2, 3}, {}, {7, 8}});

可能

int[][] tempArr = {{1, 2, 3}, {}, {7, 8}};
int[] test = flatten(tempArr);

或

int[] test = flatten(new int[][] {{1, 2, 3}, {}, {7, 8}});