#include <bits/stdc++.h>
using namespace std;
int sa1[100005],st1[100005],sc1[100005],sa2[100005],st2[100005],sc2[100005];
int pepoz[100005];
int AT[100005];
int AC[100005];
int CA[100005];
int CT[100005];
int TA[100005];
int TC[100005];
int geta1(int i, int j)
{
if(!i)return sa1[j];
return sa1[j]-sa1[i-1];
}
int gett1(int i, int j)
{
if(!i)return st1[j];
return st1[j]-st1[i-1];
}
int getc1(int i, int j)
{
if(!i)return sc1[j];
return sc1[j]-sc1[i-1];
}
int geta2(int i, int j)
{
if(!i)return sa2[j];
return sa2[j]-sa2[i-1];
}
int getat(int i, int j)
{
if(!i)return AT[j];
return AT[j]-AT[i-1];
}
int getac(int i, int j)
{
if(!i)return AC[j];
return AC[j]-AC[i-1];
}
int getca(int i, int j)
{
if(!i)return CA[j];
return CA[j]-CA[i-1];
}
int getct(int i, int j)
{
if(!i)return CT[j];
return CT[j]-CT[i-1];
}
int getta(int i, int j)
{
if(!i)return TA[j];
return TA[j]-TA[i-1];
}
int gettc(int i, int j)
{
if(!i)return TC[j];
return TC[j]-TC[i-1];
}
int cate(int i, int j)
{
if(!i)return pepoz[j];
return pepoz[j]-pepoz[i-1];
}
int gett2(int i, int j)
{
if(!i)return st2[j];
return st2[j]-st2[i-1];
}
int getc2(int i, int j)
{
if(!i)return sc2[j];
return sc2[j]-sc2[i-1];
}
bool samea(int i, int j)
{
return geta1(i,j)==geta2(i,j);
}
bool samet(int i, int j)
{
return gett1(i,j)==gett2(i,j);
}
bool samec(int i, int j)
{
return getc1(i,j)==getc2(i,j);
}
void init(string a, string b)
{
int i,n;
n=a.length();
sa1[0]=(a[0]=='A');
st1[0]=(a[0]=='T');
sc1[0]=(a[0]=='C');
for(i=1;i<n;i++)
{
sa1[i]=sa1[i-1];
st1[i]=st1[i-1];
sc1[i]=sc1[i-1];
if(a[i]=='A')sa1[i]++;
else if(a[i]=='T')st1[i]++;
else sc1[i]++;
}
sa2[0]=(b[0]=='A');
st2[0]=(b[0]=='T');
sc2[0]=(b[0]=='C');
pepoz[0]=(a[0]==b[0]);
i=0;
if(a[i]=='A')
{
if(b[i]=='T')AT[i]++;
else if(b[i]=='C')AC[i]++;
}
if(a[i]=='C')
{
if(b[i]=='A')CA[i]++;
else if(b[i]=='T')CT[i]++;
}
if(a[i]=='T')
{
if(b[i]=='A')TA[i]++;
else if(b[i]=='C')TC[i]++;
}
for(i=1;i<n;i++)
{
sa2[i]=sa2[i-1];
st2[i]=st2[i-1];
sc2[i]=sc2[i-1];
if(b[i]=='A')sa2[i]++;
else if(b[i]=='T')st2[i]++;
else sc2[i]++;
pepoz[i]=pepoz[i-1]+(a[i]==b[i]);
AT[i]=AT[i-1];
AC[i]=AC[i-1];
CA[i]=CA[i-1];
CT[i]=CT[i-1];
TA[i]=TA[i-1];
TC[i]=TC[i-1];
if(a[i]=='A')
{
if(b[i]=='T')AT[i]++;
else if(b[i]=='C')AC[i]++;
}
if(a[i]=='C')
{
if(b[i]=='A')CA[i]++;
else if(b[i]=='T')CT[i]++;
}
if(a[i]=='T')
{
if(b[i]=='A')TA[i]++;
else if(b[i]=='C')TC[i]++;
}
}
}
int get_distance(int x, int y)
{
if(!samea(x,y)||!samet(x,y)||!samec(x,y))return -1;
int swps=0;
int At,Ac,Ca,Ct,Ta,Tc;
int mac,mat,mct;
At=getat(x,y);Ac=getac(x,y);
Ca=getca(x,y);Ct=getct(x,y);
Ta=getta(x,y);Tc=gettc(x,y);
mat=min(At,Ta);
mac=min(Ac,Ca);
mct=min(Ct,Tc);
At-=mat;Ta-=mat;
Ac-=mac;Ca-=mac;
Ct-=mct;Tc-=mct;
swps=mat+mac+mct;
swps+=2*min({Ac,Ta,Ct});
swps+=2*min({At,Tc,Ca});
return swps;
}
