/*************************************************************************    > File Name: 18_PrintMatrixClock.c    > Author: Juntaran    > Mail: JuntaranMail@gmail.com    > Created Time: 2016年08月30日 星期二 17时32分28秒 ************************************************************************/#include <stdio.h>#include <stdlib.h>#define COL 4#define ROW 1void PrintMatrixCircle(int nums[][COL], int col, int row, int start){    // 从左到右打一行    for (int i = start; i < col-start; ++i)    {        int number = nums[start][i];        printf("%d ", number);    }        // 从上到下打一列    if (start < row-start-1)    {        for (int i = start + 1; i < row-start; ++i)        {            int number = nums[i][start];            printf("%d ", number);        }    }        // 从右到左打一行    if (start < col-start-1 && start < row-start-1)    {        for (int i = col-start-2; i >= start; --i)        {            int number = nums[row-start-1][i];            printf("%d ", number);        }    }        // 从下到上打一列    if (start < col-start-1 && start < row-start-2)    {        for (int i = row-start-2; i >= start + 1; --i)        {            int number = nums[i][start];            printf("%d ", number);        }    }}void PrintMatrixClock(int nums[][COL], int col, int row){    if (nums==NULL || col<=0 || row<=0)        return;    int start = 0;        while (col>start*2 && row>start*2)    {        PrintMatrixCircle(nums, col, row, start);        ++start;    }}int main(){    int nums[ROW][COL] = {{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}};        PrintMatrixClock(nums, COL, ROW);        return 0;}