顺时针打印矩阵

#include <stdio.h>

#include<assert.h>
/*顺时针打印矩阵*/
/*步骤：
 * 1、确定打几圈，有行或列中，小的那个决定 int i=（n+1）/2
 * 2、写每一圈的打印逻辑
*/


#define N 3  /*N==col*/
/*打印一圈的逻辑*/
/*row:行   col：列
time:用来记录打印了几圈*/

/*打印每一圈的逻辑*/
void printMatrix(int (*str)[N],int row,int col,int time)
{
    int x_start,y_start,x_end,y_end;
    x_start=y_start=0;
    x_end = col-1;
    y_end = row-1;
    int i,j,k;

    for(k=0;k<time;k++)
    {
        for(i=x_start;i<=x_end;i++)  printf("%d ",str[x_start][i]);
        for(j=y_start+1;j<=y_end;j++)  printf("%d ",str[j][x_end]);
        if(x_start < x_end && y_start < y_end){
            for(i=x_end-1;i>=x_start;i--)  printf("%d ",str[y_end][i]);
            for(j=y_end-1;j>y_start;j--)  printf("%d ",str[j][y_start]);
        }
        x_start++;
        y_start++;
        x_end--;
        y_end--;
    }
}

/*确定打印的圈数*/
void Print_num(int (*str)[N],int row,int col)
{
    int time=0;
    time = (row+1)/2>(col+1)/2?(col+1)/2:(row+1)/2;
    printMatrix(str,row,col,time);
}

int main(void)
{
    int str[4][3] = {{1,2,3},{4,5,6},{7,8,9},{10,11,12}};

    Print_num(str,4,3);

    return 0;
}