while(v!=0)
{
temp=u%v;
u=v;
v=temp;
}
printf("Their greatest common divisor is %i\n",u);
return 0;
}
将一个数的数字的次序倒转过来输出
#include <stdio.h>

int main(void)
{
 int number,right_digit;
 printf("Enter your number.\n");

 scanf("%i",&number);
 while(number!=0)
 {
   right_digit=number%10;
   printf("%i",right_digit);
   number=number/10;
 }
 printf("\n");
 return 0;

}
求一个整数的各个位上数的和：
#include <stdio.h>

int main(void)
{
 int number,tmp,count=0,no;

 printf("Enter a int number: ");
     scanf("%i",&number); 
  no=number;
 while(number!=0)
 {
  tmp=number%10;
  count+=tmp;
     number=number/10;
 }
 printf("The count of %i is %i.\n",no,count);
 return 0;
}