44.将一个数各个偶数位取出，并从低位往高位输出

#include<stdio.h>
unsigned long fun(unsigned long n)
{
unsigned long x = 0;
int t;
while (n)
{
t = n % 10;
if (t % 2 == 0)
x = x * 10 + t;
n = n / 10;
}
printf("%ld\n", x);
getchar();
return x;
}
int main()
{
unsigned long n = -1;
while (n > 99999999 || n < 0)
{
printf("Please input(0<n<999999999):");
scanf_s("%ld", &n);

}
printf("\nThe result is:%ld\n", fun(n));
getchar();
return 0;
}