#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int repword_count(char str[], int mid, int len) {
    int start1 = mid - 1, end1 = mid + 1;    //奇数情况,从中间向两边判断
    int count1 = 1;
    while (start1 >= 0 && end1 < len) {

        if (str[start1] == str[end1]) {
            count1 += 2;
            start1--;
            end1++;
        } else {
            break;
        }
    }

    int start2 = mid, end2 = mid + 1;        //偶数情况
    int count2 = 0;
    while (start2 >= 0 && end2 < len) {
        if (str[start2] == str[end2]) {
            count2 += 2;
            start2--;
            end2++;
        } else {
            break;
        }
    }

    return count1 > count2 ? count1 : count2;    //取两种情况的最大值
}
int main() {
    char* str = (char*)malloc(sizeof(char) * 350);
    int max = 1;
    while (~scanf("%s", str)) {
        int len = strlen(str);

        int tem = 0;
        int i = 0;
        for (i = 0; i < len - 1; i++) {
            tem = repword_count(str, i, len);
            max = max < tem ? tem : max;
        }
    }
    printf("%d", max);
}