#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization("unroll-loops")
/// author: LilPluton auuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
#define OPT ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pb push_back
#define arr array
#define vll vector<int>
#define segment_tree int l=n*2,r=l+1,mid=(b+e)/2
#define fi first
#define se second
#define rep(i,j,k) for(int i = j; i <= k; ++i)
#define all(a) a.begin(),a.end()
#define pii pair<int,int>
#define endll '\n'
using namespace std;
const int N = 1e5 + 5;
int n, pref[N];
vector<int>ac,at,ca,ct,ta,tc;
void init(string a,string b)
{
a = '#' + a;
b = '#' + b;
n = a.size();
ac.assign(n + 1,0);
at.assign(n + 1,0);
ca.assign(n + 1,0);
ct.assign(n + 1,0);
ta.assign(n + 1,0);
tc.assign(n + 1,0);
for(int i = 1; i <= n; ++i)
{
ac[i] = ac[i - 1];
at[i] = at[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] == 'C') ac[i]++;
if(b[i] == 'T') at[i]++;
}
if(a[i] == 'C')
{
if(b[i] == 'A') ca[i]++;
if(b[i] == 'T') ct[i]++;
}
if(a[i] == 'T')
{
if(b[i] == 'A') ta[i]++;
if(b[i] == 'C') tc[i]++;
}
}
}
int get_distance(int x, int y)
{
int ans = 0;
int acc = ac[y + 1] - ac[x];
int att = at[y + 1] - at[x];
int caa = ca[y + 1] - ca[x];
int ctt = ct[y + 1] - ct[x];
int taa = ta[y + 1] - ta[x];
int tcc = tc[y + 1] - tc[x];
if(acc + att != taa + caa) {return -1;}
if(caa + ctt != acc + tcc) {return -1;}
if(taa + tcc != att + ctt) {return -1;}
ans += min(acc, caa) + min(att, taa) + min(tcc, ctt);
return ans;
}
