#include<bits/stdc++.h>
//#include"prize.h"
using namespace std;
vector<int> ta,tc,ac,at,ca,ct;
vector<int> pret1,prea1,prec1,pret2,prea2,prec2;
//t a,c a t,c c a,t
void init(string a, string b)
{
int n=a.size()+1;
pret1.resize(n),prea1.resize(n),prec1.resize(n),pret2.resize(n),prea2.resize(n),prec2.resize(n);
ta.resize(n),tc.resize(n),ac.resize(n),at.resize(n),ca.resize(n),ct.resize(n);
pret1[0]=0,pret2[0]=0,prea1[0]=0,prea2[0]=0,prec1[0]=0,prec2[0]=0;
ta[0]=0,tc[0]=0,ca[0]=0,ct[0]=0,ac[0]=0,at[0]=0;
for(int x=1;x<n;x++)
{
pret1[x]=pret1[x-1],prea1[x]=prea1[x-1],prec1[x]=prec1[x-1];
if(a[x-1]=='T')
pret1[x]++;
if(a[x-1]=='C')
prec1[x]++;
if(a[x-1]=='A')
prea1[x]++;
pret2[x]=pret2[x-1],prea2[x]=prea2[x-1],prec2[x]=prec2[x-1];
if(b[x-1]=='T')
pret2[x]++;
if(b[x-1]=='C')
prec2[x]++;
if(b[x-1]=='A')
prea2[x]++;
ta[x]=ta[x-1],tc[x]=tc[x-1];
at[x]=at[x-1],ac[x]=ac[x-1];
ca[x]=ca[x-1],ct[x]=ct[x-1];
if(a[x-1]=='A' && b[x-1]=='C')
ac[x]++;
if(a[x-1]=='A' && b[x-1]=='T')
at[x]++;
if(a[x-1]=='T' && b[x-1]=='C')
tc[x]++;
if(a[x-1]=='T' && b[x-1]=='A')
ta[x]++;
if(a[x-1]=='C' && b[x-1]=='A')
ca[x]++;
if(a[x-1]=='C' && b[x-1]=='T')
ct[x]++;
}
}
int get_distance(int y, int x)
{
x++,y++;
if(prea1[x]-prea1[y-1]==prea2[x]-prea2[y-1] && pret1[x]-pret1[y-1]==pret2[x]-pret2[y-1] && prec1[x]-prec1[y-1]==prec2[x]-prec2[y-1])
{
int ans=0,cur=0;
ans=min(ac[x]-ac[y-1],ca[x]-ca[y-1])+min(at[x]-at[y-1],ta[x]-ta[y-1])+min(ct[x]-ct[y-1],tc[x]-tc[y-1]);
cur=max(ac[x]-ac[y-1],ca[x]-ca[y-1])+max(at[x]-at[y-1],ta[x]-ta[y-1])+max(ct[x]-ct[y-1],tc[x]-tc[y-1])-ans;
ans+=(cur/3)*2;
return ans;
}
else
return -1;
}
