如何让这个2D阵列旋转到正确的90度?

时间:2014-04-09 22:10:24

标签: java arrays rotation 2d

所以我有一个2D数组,它应该向右旋转90度,但它向左旋转。真的无法找出原因

公共类CrackCode16 {

public static void main (String args[]){
    int [] [] oldarray = new int [3][3];

    int value = 1;

    for (int i = 0; i < 3; i++){
        for (int j =0; j<3; j++){
            oldarray[i][j] = value;
            value++;
        }
    }


    for (int i = 0; i < 3; i++){
        for (int j =0; j<3; j++){
            System.out.print(oldarray[i][j] + "\t");
        }
        System.out.println("");
    }


    oldarray = rotate(oldarray, 3);


    System.out.println("");
    for (int i = 0; i < 3; i++){
        for (int j =0; j<3; j++){
            System.out.print(oldarray[i][j] + "\t");
        }
        System.out.println("");
    }

}

public static int [][] rotate (int [][] passedIn, int n){

    int [][] newarray = new int [n][n];

    for (int i = 0; i < n; i++){
        for (int j =0; j<n; j++){
            newarray[i][j] = passedIn [j][n-1-i];
        }
    }   

    return newarray;
}

}

输出:

1 2 3
4 5 6
7 8 9

3 6 9
2 5 8
1 4 7

1 个答案:

答案 0 :(得分:1)

newArray[i][j] = passedIn [n-1-j][i];

而不是

newarray[i][j] = passedIn [j][n-1-i];

此外,在使用Java8时,您可以考虑使用Stream来打印数组:

Stream.of(oldarray).forEach(e -> System.out.println(Arrays.toString(e)));