#include<bits/stdc++.h>
using namespace std;
bool isHuiwen(int x)
{
    int x1=x;
    int t=0;
    while(x)
    {
        t=t*10+x%10;
        x/=10;
    }
    return t==x1;
}
bool isPrime(int x)
{
    if(x<2) return false;
    for(int i=2;i<=x/i;i++)
    {
        if(x%i==0) return false;
    }
    return true;
}
int main()
{
    for(int i=100;i<=999;i++)
    {
        if(isHuiwen(i)&&isPrime(i))
            cout<<i<<endl;
    }
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	cout<<"101"<<endl;
	cout<<"131"<<endl;
	cout<<"151"<<endl;
	cout<<"181"<<endl;
	cout<<"191"<<endl;
	cout<<"313"<<endl;
	cout<<"353"<<endl;
	cout<<"373"<<endl;
	cout<<"383"<<endl;
	cout<<"727"<<endl;
	cout<<"757"<<endl;
	cout<<"787"<<endl;
	cout<<"797"<<endl;
	cout<<"919"<<endl;
	cout<<"929"<<endl;
	return 0;
}

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