3include<stdio.h>
int isPalindrome(int num)
{
    int temp=num, rev=0;
    while(temp>0)
    {
        rev=rev*10+(temp%10);
        temp/=10;
    }
    return rev==num;
}
int main()
{
    int n;
    if(scanf("%d", &n)!=1)
    {
        printf("Invalid input ");
        return 0;
    }
    if(n<0)
    {
        printf("Invalid input");
        return 0;
    }
    n++;
    while(!isPalindrome(n))
    {
        n++;
    }
    prrintf("%d",n);
    return 0;
}