#include<stdio.h>
#define fin  "pscpld.in"
#define fout "pscpld.out"
#define Nmax 2100001
#define Max  1100001

#define FL
#define DBGx

int N,len[Nmax];
char v[Nmax];

long long ret;

int main() 
{
	int i,a,b,poz;
	char buff[Max];
	
	freopen(fin,"r",stdin); 
#ifdef FL
	freopen(fout,"w",stdout);
#endif
	fgets(buff,Max,stdin);
	
	N=1; v[1]=' ';

	i=0;

	while (buff[i]!='\n' && buff[i]!=EOF) 
	{
		v[++N]=buff[i++];
		v[++N]=' ';
	}

	a=1; b=3;

	len[2]=1;

	for (i=3;i<=N;++i) 
	{
#ifdef DBG
		printf("%d: %d %d\n",i,a,b);
#endif
		if (i<=b)
		{
			poz=b-i;
	
			if (i+len[a+poz]>=b)
			{
				len[i]=b-i;
				b=i+len[i];
				a=i-len[i];
				while (v[a-1]==v[b+1] && a>1)
				{
					++len[i];
					++b;
					--a;
				}
			}
			else
				len[i]=len[a+poz];
		}
		else
		{
			len[i]=0;
			a=i; b=i;
			while (v[a-1]==v[b+1] && a>1)
			{
				++len[i];
				++b;
				--a;
			}
		}
#ifdef DBG
		for (int j=1;j<=N;++j)
			printf("%c ",v[j]);
		printf("\n");
		for (int j=1;j<=N;++j)
			printf("%d ",len[j]);
		printf("\n\n");
#endif
	
	}
	
	
	for (i=1;i<=N;++i)
		if ( v[i] == ' ' )	
			ret+=(len[i]+1)/2;
		else 
		{
			ret+=len[i]/2;
			++ret;
		}
			
	printf("%lld\n",ret);

	return 0;
}