LeetCode:59. Spiral Matrix II 螺旋矩阵 II（C语言）

ゝ一世哀愁。 2023-07-05 10:21 112阅读 0赞

**题目描述：**  
给定一个正整数 n，生成一个包含 1 到 n2 所有元素，且元素按顺时针顺序螺旋排列的正方形矩阵。

示例:

输入: 3  
输出:  
\[  
\[ 1, 2, 3 \],  
\[ 8, 9, 4 \],  
\[ 7, 6, 5 \]  
\]

来源：力扣（LeetCode）  
链接：https://leetcode-cn.com/problems/spiral-matrix-ii  
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。  
**解答：**

/** * Return an array of arrays of size *returnSize. * The sizes of the arrays are returned as *returnColumnSizes array. * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free(). */
    
    int** generateMatrix(int n, int* returnSize, int** returnColumnSizes)
    { 
        *returnSize = n;//返回行数
    
        int **ret = (int**)malloc(sizeof(int*)*n);
        int i = 0;
        int j = 0;
        int count = 1;
        int left = 0;
        int right = n-1;
        int top = 0;
        int down = n-1;
        
        for(i = 0;i<n;i++)
        { 
            ret[i] = (int*)malloc(sizeof(int)*n);
        }
    
        while(left < right)
        { 
            for(j = left;j<=right;j++)
            { 
                ret[top][j] = count;
                count++;
            }
    
            top++; 
    
            for(i = top;i<=down;i++)
            { 
                ret[i][right] = count;
                count++;
            }
            
            right--; 
    
            for(j = right;j>=left;j--)
            { 
                ret[down][j] = count;
                count++;
            }
    
            down--;
    
            for(i = down;i>=top;i--)
            { 
                ret[i][left] = count;
                count++;
            }
            
            left++;
        }
    
        if(left == right)
        { 
            ret[top][left] = count;
        }
    
        *returnColumnSizes = malloc(sizeof(void*)*n);
        for(i = 0;i<n;i++)
        { 
            (*returnColumnSizes)[i] = n;//返回的每行的长度
        }
    
        return ret;
    }

**运行结果：**  
![在这里插入图片描述][20200214000317323.png]

[20200214000317323.png]: https://img-blog.csdnimg.cn/20200214000317323.png