#include<stdio.h>
#include<string.h>
#include<stdlib.h>
int main(void){
int a,b;
int pout=3;
scanf("%d %d",&a,&b);
for(int i=a;i<=b;i++){
if(i==23){pout--;}
if(i==24){pout--;}
if(i==25){pout--;}
}
printf("%d\n",pout);
}