c - 旋转 90 度二维字符数组

Question

我真的看不出这段代码有什么问题？

我正在尝试获取:

w 3 l l  
d o n 3
g a m 3
o v 3 r 

来自:

l 3 3 r
l n m 3
3 0 4 v
w d g 0

这是我的代码:

int main() {
    printf("Size of array : ");
    int n;
    scanf("%d", &n);
    printf("Cases : \n");
    char **array = (char**)malloc(n * sizeof(char));
    for (i = 0; i < n; i++)
        array[i] = (char*)malloc(n * sizeof(char));
    int j;
    // Words input
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            scanf("%c", &array[i][j]);
        }
    }
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n\n");

    // Transpose of the array
    for (i = 0; i <= n; i++) {
        for (j = i + 1; j < n; j++) {
            char tmp = array[i][j];
            array[i][j] = array[j][i];
            array[j][i] = tmp;
        }
    }

    // Display the transposed array
    printf("Transposed array \n");
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n");
    printf("\n");
    // Swap the columns
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n / 2; j++) {
            char tmp = array[i][j];
            array[i][j] = array[i][n - 1 - j];
            array[i][n - 1 - j] = tmp;
        }
    }
    // Display after rotation
    printf("After rotation\n");
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n");
    return 0;
}

是语法问题吗？ 它似乎可以很好地处理整数...

int main() {
    printf("Size of array : ");
    int n;
    scanf("%d", &n);
    printf("Cases : \n");
    char **array = (char**)malloc(n * sizeof(char));
    for (i = 0; i < n; i++)
        array[i] = (char*)malloc(n * sizeof(char));
    int j;
    // Words input
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            scanf("%c", &array[i][j]);
        }
    }
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n\n");
    // Transpose of the array
    for (i = 0; i <= n; i++ ) {
        for (j = i + 1; j < n; j++ ) {
            char tmp = array[i][j];
            array[i][j] = array[j][i];
            array[j][i] = tmp;
        }
    }
    // Display the transposed array
    printf("Transposed array \n");
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n");
    printf("\n");
    // Swap the columns
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n / 2; j++) {
            char tmp = array[i][j];
            array[i][j] = array[i][n - 1 - j];
            array[i][n - 1 - j] = tmp;
        }
    }
    // Display after rotation
    printf("After rotation\n");
    for (i = 0; i <= n; i++) {
        for (j = 0; j < n; j++) {
            printf("%c", array[i][j]);
        }
    }
    printf("\n");
    return 0;
}                                                                      

Answer 1

正如@Some程序员兄弟所指出的，有两个主要问题:

首先，您没有分配“n x n 字符矩阵”意义上的“二维数组”，但您似乎分配了一个包含 n 个指针的数组，每个指针都指向一个包含 n 个字符的序列。所以你应该首先分配n个指针，即char **array = malloc(n * sizeof(char*)) .

其次，您使用 i <= n 反复超出数组边界自始至终;使用i < n反而。顺便说一句:你没有声明 i和j ...

解决这个问题后，您的程序就可以运行了:

int main()
{
    printf("Size of array : ");
    int n;
    scanf("%d", &n);
    printf("Cases : \n");
    char **array = malloc(n * sizeof(char*));
    for (int i = 0; i < n; i++)
        array[i] = malloc(n * sizeof(char));
    int j;
    // Words input
    for (int i = 0; i < n; i++)
    {
        for (j = 0; j < n; j++)
        {
            scanf("%c", &array[i][j]);
        }
    }
    for (int i = 0; i < n; i++)
    {
        for (j = 0; j < n; j++)
        {
            printf("%c", array[i][j]);
        }
        printf("\n");
    }
    printf("\n\n");

    // Transpose of the array
    for (int i = 0; i < n; i++ )
    {
        for (int j = i + 1; j < n; j++ )
        {
            char tmp = array[i][j];
            array[i][j] = array[j][i];
            array[j][i] = tmp;
        }
    }

    // Display the transposed array
    printf("Transposed array \n");
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            printf("%c", array[i][j]);
        }
        printf("\n");
    }
    printf("\n");
    printf("\n");
    // Swap the columns
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n / 2; j++)
        {
            char tmp = array[i][j];
            array[i][j] = array[i][n - 1 - j];
            array[i][n - 1 - j] = tmp;
        }
    }
    // Display after rotation
    printf("After rotation\n");
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            printf("%c", array[i][j]);
        }
        printf("\n");
    }
    printf("\n");
    return 0;
}