#include<stdio.h>

void main(){
	int i,g,s,b,q;
	
	for(i=1000;i<=9999;i++){
		g=i%10;
		s=i/10%10;
		b=i/100%10;
		q=i/1000;
		if(g==q&&s==b){
			printf("%d\n",i); 
		}
	}

}
/**************************************************************
	Problem: 1447
	User: admin
	Language: C
	Result: Accepted
	Time:5 ms
	Memory:1036 kb
****************************************************************/