#include<bits/stdc++.h>
#define ll long long
using namespace std;

const int maxn = 20005;

int n,m;
string S,T;

int match(int h,int i,int j)
{
	if(S[i]!=T[j]) return -1;
	if(j==m) return i;
	
	if(h==0)
	{
		if(i==n) return -1;
		if(S[i+1]!=T[j+1]) return -1;
		//i,ri
		//j,rj
		int ri,rj;
		
		ri=i;
		while(ri<=n && S[ri]==S[i+(ri-i)%2])ri++;
		ri--;
		
		rj=j;
		while(rj<=m && T[rj]==T[j+(rj-j)%2])rj++;
		rj--;
		
		if(rj==m)
		{
			return i+1;
		}
		else //rj!=m
		{
			if( (ri-i)%2 != (rj-j)%2 ) return -1;
			if( ri-i > rj-j ) return -1;
			return match(0,ri,rj);
		}
	}
	else if(i-1>0 && S[i-1]==T[j+1])
	{
		int ri,rj;
		
		ri=i;
		while(ri<=n && S[ri]==S[i-1+(ri-i+1)%2])ri++;
		ri--;
		
		rj=j;
		while(rj<=m && T[rj]==T[j+(rj-j)%2])rj++;
		rj--;
		
		if(rj==m)
		{
			return i;
		}
		else //rj!=m
		{
			if( (ri-i+1)%2 != (rj-j)%2 ) return -1;
			if( ri-i+1 > rj-j ) return -1;
			return match(0,ri,rj);
		}
		
	}
	return -1;
}
int ri[maxn];

int main()
{
	ios_base::sync_with_stdio(false);
	
	cin>>S>>T;
	n=S.size(); m=T.size();
	S=' '+S; T=' '+T;
	
	string tempt;
	for(int i=1;i<=m;i++)
	{
		if(T[i]!=T[i-1]) tempt=tempt+T[i];
	}
	T=tempt;
	m=T.size();
	T=' '+T;
	
	for(int i=1;i<=n;i++) ri[i]=n+1;
	for(int i=n;i>=1;i--)
	{
		int j=match(0,i,1);
		if(j!=-1) ri[i]=min(ri[i],j);
		if(i-1>0) 
		{
			j=match(1,i,1);
			if(j!=-1) ri[i-1]=min(ri[i-1],j);
		}
	}
	
	ll ans=0;
	for(int i=n,R=n+1;i>=1;i--)
	{
		if(ri[i]!=n+1) R=min(R,ri[i]);
		if(R!=n+1) ans+=n-R+1;
	}
	cout<<ans<<endl;
	
	return 0;
}