#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 100001;
int at[maxn], ac[maxn], ca[maxn], ct[maxn], ta[maxn], tc[maxn];
void init(string a, string b) {
for (int i = 0; i < a.size(); i++) {
string x;
x.push_back(a[i]);
x.push_back(b[i]);
if (x == "AT")
at[i + 1] = 1;
else if (x == "AC")
ac[i + 1] = 1;
else if (x == "CA")
ca[i + 1] = 1;
else if (x == "CT")
ct[i + 1] = 1;
else if (x == "TA")
ta[i + 1] = 1;
else if (x == "TC")
tc[i + 1] = 1;
}
int len = a.size();
auto psum = [len](int arr[]) {
for (int i = 1; i <= len; i++) arr[i] += arr[i - 1];
};
psum(at);
psum(ac);
psum(ca);
psum(ct);
psum(ta);
psum(tc);
}
int get_distance(int x, int y) {
auto qry = [x, y](int arr[]) { return arr[y + 1] - arr[x]; };
int ati = qry(at), aci = qry(ac), cai = qry(ca), cti = qry(ct), tai = qry(ta),
tci = qry(tc);
int ans = 0;
int val = min(ati, tai);
ans += val;
ati -= val, tai -= val;
val = min(aci, cai);
ans += val;
aci -= val, cai -= val;
val = min(cti, tci);
ans += val;
cti -= val, tci -= val;
val = min({aci, cti, tai});
aci -= val, cti -= val, tai -= val;
ans += 2 * val;
val = min({cai, ati, tci});
cai -= val, ati -= val, tci -= val;
ans += 2 * val;
if (ati > 0 || aci > 0 || cai > 0 || cti > 0 || tai > 0 || tci > 0) return -1;
return ans;
}
