Java

Question

那么，它应该如何运作。我输入 "n" 和 "m" 来制作分辨率为 n*m 的二维矩阵。我需要将它向右旋转 90 度，使其看起来像在绘画中制作的图像：

我写了一些代码，但我真的不能让它工作 - 看起来很容易，但每次我尝试让它工作时，我都会 "outofboundsexception"。这是：

 import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner s1 = new Scanner(System.in);
        int n = s1.nextInt();
        int m = s1.nextInt();
        System.out.println();
        int[][] array = new int[n][m];
        int[][] ar = new int[n][m];
        for(int i = 0; i < array.length; i++) {
            for(int j = 0; j < array[n - 1].length; j++) {
                array[i][j] = s1.nextInt();
            }
        }
        System.out.println("INPUT ARRAY :");
        System.out.println();
        for(int i = 0; i < array.length; i++) {
            for (int j = 0; j < array[n - 1].length; j++) {
                System.out.print(array[i][j] + " ");
            }
            System.out.println();
        }
        /* here is the main actions with the array begin*/
        for(int i = 0; i < array.length; i++) {
            for(int j = 0; j < array[n - 1].length; j++) {
                ar[i][j]=array[n - j - 1][i];
            }
        }
        /*the end of actions with the array*/
        System.out.println("TASK ARRAY :");
        System.out.println();
        for(int i = 0; i < ar.length; i++) {
            for (int j = 0; j < rr[n - 1].length; j++) {
                System.out.print(ar[i][j] + " ");
            }
            System.out.println();
        }
    }


}

我到底做错了什么？

Answer 1

`double x1 = point.x - center.x; 双 y1 = point.y - center.y;

double x2 = x1 * Math.cos(角度) - y1 * Math.sin(角度)); 双 y2 = x1 * Math.sin(角度) + y1 * Math.cos(角度));

point.x = x2 + center.x; point.y = y2 + center.y;`

那应该变换每个点，从那里应该足够简单了。中心是 length/2

Answer 2

这是您的程序的正确版本，所有 for 循环索引均已修复，打印移至单独的方法中。

public class Main {
    static void print(String title, int[][] array) {
        System.out.println(title);
        System.out.println();
        for (int i = 0; i < array.length; i++) {
            for (int j = 0; j < array[i].length; j++) {
                System.out.print(array[i][j] + " ");
            }
            System.out.println();
        }
    }

    public static void main(String[] args) {
        Scanner s1 = new Scanner(System.in);
        int m = s1.nextInt();
        int n = s1.nextInt();
        System.out.println();
        int[][] array = new int[m][n];
        int[][] ar = new int[n][m];
        for(int i = 0; i < array.length; i++) {
            for(int j = 0; j < array[i].length; j++) {
                array[i][j] = s1.nextInt();
            }
        }

        print("INPUT ARRAY :", array);

        /* here is the main actions with the array begin*/
        for(int i = 0; i < array.length; i++) {
            for(int j = 0; j < array[i].length; j++) {
                ar[j][m - i - 1] = array[i][j];
            }
        }

        /*the end of actions with the array*/
        print("TASK ARRAY :", ar);
    }
}

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