题目挺有意思 用笨方法写了写

#include <stdio.h>
#include <math.h>
#include <malloc.h>

void chushi();
int **hui(int n);

int main(int argc, char const *argv[])
{

    int n = 0;
    printf("input number:\n");
    scanf("%d", &n);
    int r = ceil(sqrt(n));

    int **b = hui(n);
    for (int i = 0; i < r; i++)
    {
        for (int j = 0; j < r; j++)
        {
            printf("%5d ", *((int *)b + r * i + j));
        }
        printf("\n");
        printf("\n");
    }

    return 0;
}

// 逆时针旋转 第一遍
void chushi()
{
    int n = 36;
    int r = ceil(sqrt(n));
    int nums[n][n];

    for (int x = 0; x < n; x++)
    {
        for (int y = 0; y < n; y++)
        {
            nums[x][y] = 0;
        }
    }

    int j = r / 2;
    int k = r / 2;

    int f = 2;

    int i = 1;
    int c = 1;

    while (1)
    {
        for (int l = 0; l < f; l++)
        {
            nums[j][k] = i;

            i++;
            k += c;

            if (i == n + 1)
            {
                for (int x = 0; x < n; x++)
                {
                    for (int y = 0; y < n; y++)
                    {
                        printf("%3d", nums[x][y]);
                    }
                    printf("\n");
                }
                return 1;
            }
        }
        k -= c;
        i--;

        for (int l = 0; l < f; l++)
        {
            nums[j][k] = i;

            i++;
            j -= c;

            if (i == n + 1)
            {
                for (int x = 0; x < n; x++)
                {
                    for (int y = 0; y < n; y++)
                    {
                        printf("%3d", nums[x][y]);
                    }
                    printf("\n");
                }
                return 1;
            }
        }
        j += c;
        i--;

        f++;
        c = -c;
    }
}

// 逆时针旋转 第二遍
int **hui(int n)
{
    // 半径和初始坐标
    int r = ceil(sqrt(n));
    int j = r / 2;
    int k = r / 2 + r % 2 - 1;

    // 初始化
    int **nums = (int **)malloc(n * sizeof(int *));
    for (int i = 0; i < r; i++)
    {
        nums[i] = (int *)malloc(n * sizeof(int));
    }
    for (int x = 0; x < r; x++)
    {
        for (int y = 0; y < r; y++)
        {
            *((int *)nums + r * x + y) = 0;
        }
    }

    int f = 2; // 从2个开始循环

    int i = 1; // n从小到大

    int c = 1; // 符号转换器

    while (1)
    {
        for (int l = 0; l < f; l++)
        {
            *((int *)nums + r * j + k) = i;

            i++;
            k += c;

            if (i == n + 1)
            {
                return nums;
            }
        }
        k -= c;
        i--;

        for (int l = 0; l < f; l++)
        {
            *((int *)nums + r * j + k) = i;

            i++;
            j -= c;

            if (i == n + 1)
            {
                return nums;
            }
        }
        j += c;
        i--;

        f++;
        c = -c;
    }
}