题解 | #[NOIP2010]数字统计#

#include <stdio.h>
int judge( int i)
{
   int a ,count=0;
   while(i)
   { 
      a= i%10;
      i = i/10;
      if(a==2)
      {
        count++;
      }
   }
   return count;
}
int main()
{ 
    int L,R,count=0;
    scanf("%d %d",&L,&R);
    for(int i=L;i<=R;i++)
    {
       int ret = judge(i);
       count+=ret;
    }  
    printf("%d",count);
    return 0;
}