#include <stdio.h>
#include <stdlib.h>
int main(void)
{  int i,a,b,count=0;
   while(scanf("%d%d",&a,&b) != EOF)
   {
         for(i=a;i<=b;i++)
        {
         if(i%2==0)
      {
           if(i==2)count+=1;
            else count+=2;
      }
      else
      {
        if(i==1);
        else count+=1;
      }
     }
     printf("%d\n",count);
   }
      
    return 0;
}
对于下一次的输出结果会加上上一次的输出结果。求高人指点一下