#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
int a[100005], b[100005], c[100005], d[100005], e[100005], f[100005];
void init(string s, string t)
{
int len=s.length();
for (int i=0; i<len; i++)
{
a[i+1]=a[i]+(s[i]=='A' && t[i]=='C');
b[i+1]=b[i]+(s[i]=='A' && t[i]=='T');
c[i+1]=c[i]+(s[i]=='C' && t[i]=='A');
d[i+1]=d[i]+(s[i]=='C' && t[i]=='T');
e[i+1]=e[i]+(s[i]=='T' && t[i]=='A');
f[i+1]=f[i]+(s[i]=='T' && t[i]=='C');
}
}
int get_distance(int x, int y)
{
int A=a[y+1]-a[x];
int B=b[y+1]-b[x];
int C=c[y+1]-c[x];
int D=d[y+1]-d[x];
int E=e[y+1]-e[x];
int F=f[y+1]-f[x];
if (E!=A+B-C || F!=C+D-A)
return -1;
return B+D+max(A, C);
}
