#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
#include<algorithm>

using namespace std;

const int maxn = 1000000 + 10;

char ch[maxn]; 

int f[maxn];

int maxm = 0;

int ans = 0;

int main()
{
	freopen("savemzx.in","r",stdin);
	freopen("savemzx.out","w",stdout);
	scanf("%s",ch+1);
	int len = strlen(ch+1);
	f[1] = 1;
	for(int i=2;i<=len;i++)
	{
		if(ch[i]!=ch[1]) 
		{
			f[i]=i*i;
		}
		else
		{
			int j = 1;
			while(ch[i]==ch[j]&&i<=len)
			{
				f[i]=f[j]+(i-j)*(i-j);
				j++;
				i++;
			}
		}
	}
	/*
	for(int i=1;i<=len;i++)
	{
		if(f[i]>maxm)
		{
			maxm=f[i];
			cout<<maxm;
		}
	}
	*/
	sort(f+1,f+1+len);
	ans = f[len] + f[len-1];
	cout<<ans;
	return 0;
}