程序代码：

#include <stdio.h>
viod fun(unsigned long *n)
{unsigned long x=0,i; int t;
i=1;
while(*n)
    {t=*n%10;
    if(t%2!=0)
    {
        x=x+t*i; i=i*10
    }
    *n=*n/10
}*n=x
}
main()
{
    unsigned long n=-1;
    while(n>99999999||n<0)
    {
        printf("please input(0<n<100000000):");scanf("%ld",&n);
    }
fun(&n);
printf("\nthe result is:%ld\n",n);}

程序代码：

#include <stdio.h>
viod fun(unsigned long *n)
{unsigned long x=0,i; int t;
i=1;
while(*n)
    {t=*n%10;
    if(t%2!=0)
    {
        x=x+t*i; i=i*10;
    }
    *n=*n/10;
}*n=x;
}
main()
{
    unsigned long n=-1;
    while(n>99999999||n<0)
    {
        printf("please input(0<n<100000000):");scanf("%ld",&n);
    }
fun(&n);
printf("\nthe result is:%ld\n",n);}

程序代码：

#include <stdio.h>
void fun(unsigned long *n)
{unsigned long x=0,i; int t;
i=1;
while(*n)
    {t=*n%10;
    if(t%2!=0)
    {
        x=x+t*i; i=i*10;
    }
    *n=*n/10;
}*n=x;
}
main()
{
    unsigned long n=-1;
    while(n>99999999||n<0)
    {
        printf("please input(0<n<100000000):");scanf("%ld",&n);
    }
fun(&n);
printf("\nthe result is:%ld\n",n);}