#include "dna.h"
#include <bits/stdc++.h>
#define _USE_MATH_DEFINES
#define INF LLONG_MAX
#define MOD 1000000007
#define endl "\n"
#define sp " "
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define f1(i, x) for(auto &i : x)
#define f2(i, x, j) for(ll i = j; i < x; i++)
#define raya() cout << endl << "====================================" << endl
#define dbg(x) cerr << #x << ": " << x << endl;
using namespace std;
using ll = long long;
vector<int> a1, t1, c1;
vector<int> a2, t2, c2;
vector<int> diff;
string A, B;
void init(string a, string b) {
A = a;
B = b;
int n = a.size();
a1.assign(n + 1, 0);
t1.assign(n + 1, 0);
c1.assign(n + 1, 0);
a2.assign(n + 1, 0);
t2.assign(n + 1, 0);
c2.assign(n + 1, 0);
diff.assign(n + 1, 0);
for(int i = 0; i < n; i++){
if(a[i] == 'A') a1[i + 1]++;
if(a[i] == 'T') t1[i + 1]++;
if(a[i] == 'C') c1[i + 1]++;
if(b[i] == 'A') a2[i + 1]++;
if(b[i] == 'T') t2[i + 1]++;
if(b[i] == 'C') c2[i + 1]++;
if(a[i] != b[i]) diff[i + 1]++;
a1[i + 1] += a1[i];
t1[i + 1] += t1[i];
c1[i + 1] += c1[i];
a2[i + 1] += a2[i];
t2[i + 1] += t2[i];
c2[i + 1] += c2[i];
diff[i + 1] += diff[i];
}
}
int get_distance(int x, int y){
bool t = 1;
x++;
y++;
if(a1[y] - a1[x - 1] != a2[y] - a2[x - 1]){
t = 0;
}
if(t1[y] - t1[x - 1] != t2[y] - t2[x - 1]){
t = 0;
}
if(c1[y] - c1[x - 1] != c2[y] - c2[x - 1]){
t = 0;
}
if(!t){
return -1;
}
int z = diff[y] - diff[x - 1];
return (z + 1) / 2;
}
