#include<bits/stdc++.h>
#include "dna.h"
using namespace std;
vector<int> AC;
vector<int> AT;
vector<int> CA;
vector<int> CT;
vector<int> TA;
vector<int> TC;
void init(string a, string b)
{
int 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 = 0; i < n; i++)
{
AC[i+1] = AC[i];
AT[i+1] = AT[i];
CA[i+1] = CA[i];
CT[i+1] = CT[i];
TA[i+1] = TA[i];
TC[i+1] = TC[i];
if (a[i]=='A')
{
if (b[i]=='C') AC[i+1]++;
if (b[i]=='T') AT[i+1]++;
}
if (a[i]=='C')
{
if (b[i]=='A') CA[i+1]++;
if (b[i]=='T') CT[i+1]++;
}
if (a[i]=='T')
{
if (b[i]=='A') TA[i+1]++;
if (b[i]=='C') TC[i+1]++;
}
}
}
int get_distance(int y, int x)
{
int sol = 0;
int ac = AC[x+1]-AC[y];
int at = AT[x+1]-AT[y];
int ca = CA[x+1]-CA[y];
int ct = CT[x+1]-CT[y];
int ta = TA[x+1]-TA[y];
int tc = TC[x+1]-TC[y];
if (ac+at != ta+ca) return -1;
if (ca+ct != tc+ac) return -1;
if (ta+tc != at+ct) return -1;
sol += min(ac, ca) +min(at, ta) + min(ct, tc);
ac -= min(ac, ca);
at -= min(at, ta);
ca -= min(ac, ca);
ct -= min(tc, ct);
ta -= min(at, ta);
tc -= min(tc, ct);
vector<int> nn;
if (ac != 0) nn.push_back(ac);
if (at != 0) nn.push_back(at);
if (ca != 0) nn.push_back(ca);
if (ct != 0) nn.push_back(ct);
if (ta != 0) nn.push_back(ta);
if (tc != 0) nn.push_back(tc);
sort(nn.begin(), nn.end());
if (nn.size() > 2) sol += nn[1] + nn[0];
return sol;
}
