#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
    int i, j, q, k = 0;
    int count[10001] = {0};
    char arr[1001];
    int max;
    
    gets(arr);
    
    if(strlen(arr) == 1)
        max = 1;
    else{
        //最长字符串为奇数 
        for(i = 1; i < strlen(arr)-1; i++)
        {
            j = i;
            q = i;
            while(arr[--j] == arr[++q] && j >= 0 && q < strlen(arr))
            {
                count[k]++;
            }
            count[k] = count[k]*2+1;
            k++;
        }
        //最长字符串为偶数 
        for(i = 0; i < strlen(arr); i++)
        {
            j = i;
            q = i+1;
            while(arr[j] == arr[q] && j >= 0 && q < strlen(arr))
            {
                j--;
                q++;
                count[k]++;
            }
            count[k] = count[k]*2;
            k++;
        }
        
        max = count[0];
        for(i = 1; i < k; i++)
        {
            if(count[i] > max)
                max = count[i];
        }
    }
    printf("%d", max);
    
    return 0;
}