#include<cstdio>
#include<cctype>
#include<cstring>
using namespace std;
char s[205];
void perm( char *s)
{
    char aux;
    aux=s[0];
    for(int i=0;i<strlen(s)-1;i++)
        s[i]=s[i+1];
    s[strlen(s)-1]=aux;
}
bool palindrom(char *s)
{
    int i,n=strlen(s);
    for(i=0;i<strlen(s)/2;i++)
        if(s[i]!=s[strlen(s)-1-i]) return 0;
    return 1;
}
int main()
{

    freopen("palc.in","r",stdin);
    freopen("palc.out","w",stdout);
    int x,cnt=0;
    gets(s);
    int n=strlen(s);
    while(palindrom(s)==0||cnt!=n)
    {
        if(cnt==n) break;
        cnt++;
        perm(s);
        if(palindrom(s)==1) break;
    }
    if(cnt==n) printf("-1");
        else
        {
            if(cnt>n/2) cnt=n-cnt;
            printf("%d",cnt);
        }
    return 0;
}