#include<cstdio>
#include<cstring>
char b[1000001],a[2000001];
int n,i,lg=1,poz=1,s[2000001];
long long nr;
int m(int a,int b)
{
    if(a<b) return a;
    return b;
}
int main()
{
    freopen("pscpld.in","r",stdin);
    freopen("pscpld.out","w",stdout);
    gets(b);
    s[0]=1;
    n=strlen(b);
    for(i=0;i<n;i++){
        a[2*i+1]=b[i];
        a[2*i]=' ';}
    n=2*n-1;
    s[1]=1;
    nr=1;
    for(i=2;i<=n;i++){
        s[i]=1;
        if(poz+lg-1>i)
            s[i]=m(poz+lg-i,s[2*poz-i]);
        while(i-s[i]>0 && a[i-s[i]]==a[i+s[i]]) s[i]++;
        if(i%2)
            nr+=(s[i]+1)/2;
        else
            nr+=s[i]/2;
        if(s[i]+i>poz+lg) poz=i,lg=s[i];}
    printf("%lld\n",nr);
    fclose(stdout);
    return 0;
}