// nouse1.cpp : Defines the entry point for the console application.//
#include "stdafx.h"#include <stdio.h>#include <string.h>#include <math.h>
int prime(int num){ int i; if(num == 1) return 0; if(num == 2) return 1; for(i=2;i<=sqrt(num);i++) if(num % i == 0) return 0; return 1;}
int hw(int num){ int orinum = num; int newnum=0;
while(num > 0) { newnum = 10*newnum + num%10; //! num /= 10; } if(newnum == orinum) return 1; return 0;}
void main(){
int a,b; int i; int count = 0;
while(scanf("%d %d",&a,&b) != EOF) { count = 0; for(i=a;i<=b;i++) { if(hw(i)==1) { if(prime(i) == 1) count++; } }
printf("%d/n",count); }
}
