#include<bits/stdc++.h>
using namespace std;
#include "dna.h"
# define ll long long
vector<ll> at(100001),ta(100001),ac(100001),ca(100001),tc(100001),ct(100001);
void init(std::string a, std::string b) {
ll s=a.size();
for(int i=0; i<s; i++){
string ty;
ty+=a[i];
ty+=b[i];
if(ty=="AT")at[i+1]=at[i]+1;
else
at[i+1]=at[i];
if(ty=="TA") ta[i+1]=ta[i]+1;
else
ta[i+1]=ta[i];
if(ty=="AC") ac[i+1]=ac[i]+1;
else
ac[i+1]=ac[i];
if(ty=="CA") ca[i+1]=ca[i]+1;
else
ca[i+1]=ca[i];
if(ty=="TC") tc[i+1]=tc[i]+1;
else
tc[i+1]=tc[i];
if(ty=="CT") ct[i+1]=ct[i]+1;
else
ct[i+1]=ct[i];
}
}
int get_distance(int x, int y) {
x++;
y++;
ll AT=at[y]-at[x-1],TA=ta[y]-ta[x-1],AC=ac[y]-ac[x-1],CA=ca[y]-ca[x-1],TC=tc[y]-tc[x-1],CT=ct[y]-ct[x-1];
ll pos1a=AT+AC,pos1t=TA+TC,pos1c=CA+CT;
ll pos2a=TA+CA,pos2t=AT+CT,pos2c=AC+TC;
if(pos1a!=pos2a || pos1c!=pos2c || pos1t!=pos2t) return -1;
ll ans=AT+TA+AC+CA+TC+CT;
ll once=0;
once+=min(AT,TA);
AT-=min(AT,TA);
TA-=min(AT,TA);
once+=min(AC,CA);
AT-=min(AC,CA);
TA-=min(AC,CA);
once+=min(TC,CT);
AT-=min(TC,CT);
TA-=min(TC,CT);
once+=min({AT,CA,TC});
once+=min({TA,AC,CT});
return ans-once;
}
