C语言：给一个不过于5的正整数。要求：1求他是几位数2逆序打印各位数字。

main( )
{
long a,b,c,d,e,x;
scanf("%ld",&x);
a=x/10000;/*分解出万位*/
b=x%10000/1000;/*分解出千位*/
c=x%1000/100;/*分解出百位*/
d=x%100/10;/*分解出十位*/
e=x%10;/*分解出个位*/
if (a!=0) printf("there are 5, %ld %ld %ld %ld %ld\n",e,d,c,b,a);
else if (b!=0) printf("there are 4, %ld %ld %ld %ld\n",e,d,c,b);
else if (c!=0) printf(" there are 3,%ld %ld %ld\n",e,d,c);
else if (d!=0) printf("there are 2, %ld %ld\n",e,d);
else if (e!=0) printf(" there are 1,%ld\n",e);
}

#include <stdio.h>
void main()
{
int n=0,num1,num2=0;
printf("input a number:");
scanf("%d",&num1);
while(num1)
{
num2=num2*10+num1%10;
num1/=10;
n++;
}
printf("%d位数，%d\n",n,num2);
}

#include <stdio.h>
main()
{
int a[5];
int i