(PAT)一个函数判断给定正整数的各位数字之和是否等于5；另一个函数统计给定区间内有多少个满足上述要求的整数，并计算这些整数的和

#include <stdio.h>

int is( int number );
void count_sum( int a, int b );

int main()
{
    
    
    int a, b;

    scanf("%d %d", &a, &b);
    if (is(a)) printf("%d is counted.\n", a);
    if (is(b)) printf("%d is counted.\n", b);
    count_sum(a, b);

    return 0;
}
int is( int number )
{
    
    
      int count = 0, yu;
      while(number >= 10)
      {
    
    
          yu = number % 10;
          count += yu;
          number = (int)(number/10);
      }
      count += number;
      if(count == 5) return 1;
      else return 0;
}

void count_sum( int a, int b )
{
    
    
       int count = 0;
       int sum = 0;
       for(int i = a; i <= b; i++)
       {
    
    
           if(is(i))
           {
    
    
               count++;
               sum = sum + i;
           }
       }
       printf("count = %d, sum = %d",count,sum);
}