#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(){
   int a,b,c,ans;
   scanf("%d %d %d",&a,&b,&c);
   if(((a < b)||(c < b))&&(a != b)&&(b != c)){
      //printf("%d\n",b-a);
      if(a < c )ans = b-c;
      else ans = b-a;
   }
   printf("%d\n",ans);
}