#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; bool a(int n){ if(n<=1)return 0; for(int i=2;i*i<=n;i++){ if(n%i==0)return 0; } return 1; } bool b(int n){ int m=n,k; n=0; while(m){ n=n*10+m%10; m/=10; } if(a(n))return 1; else return 0; } int main(){ int n,m,bbb; bool aaaaaa=0; cin>>m>>n; for(int i=m;i<=n;i++){ if(a(i)&&b(i)){cout<<i; bbb=i;aaaaaa=1; break;} } for(int i=bbb+1;i<=n;i++){ if(a(i)&&b(i))cout<<","<<i; } if(aaaaaa==0)cout<<"No"; return 0; }