ten_thousand=num/10000什么意思

5.7 给定一个不多于5位的正整数，要求：① 求它是几位数；② 分别打印出每一位数字；③ 按逆序打印出各位数字。例如原数为321，应输出123。
#include
<stdio.h>
main()
{
long int num;
int
indiv,ten,hundred,thousand,ten_thousand,place;
/*分别代表个位、十位、百位、千位、万位和位数*/
printf("请输入一个整数（0~99999）：");
scanf("%ld",&num);
if
(num>9999) place=5;
else
if(num>999) place=4;
else
if(num>99) place=3;
else
if(num>9) place=2;
else
place=1;
printf("place
=%d\n", place);
ten_thousand=num/10000;
thousand=num/1000%10;
hundred=num/100%10;
ten=num%100/10;
indiv=num%10;
switch(place)
{
case 5:
printf("%d,%d,%d,%d,%d",ten_thousand,thousand,hundred,ten,indiv);
printf("\n反序数字为；");
printf("%d%d%d%d%d\n",indiv,ten,hundred,thousand,ten_thousand);
break;
case 4:
printf("%d,%d,%d,%d",thousand,hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d%d\n",indiv,ten,hundred,thousand);
break;
case 3: printf("%d,%d,%d",hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d\n",indiv,ten,hundred);
break;
case 2:
printf("%d,%d",ten,indiv);
printf("\n反序数字为：");
printf("%d%d\n",indiv,ten);
break;
case 1: printf("%d",indiv);
printf("\n反序数字为：");
printf("%d\n",indiv);
break;
}
}
有没有更简洁的方法？