#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
const int N = 100010;
struct Data {
int a[3][3];
int* operator[](int u) {
return a[u];
}
Data operator-(const Data &o) const {
Data res;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
res[i][j] = a[i][j] - o.a[i][j];
}
}
return res;
}
};
Data sum[N];
void init(std::string a, std::string b) {
map<char, int> m;
m['A'] = 0;
m['T'] = 1;
m['C'] = 2;
for (int i = 0; i < (int)a.size(); i++) {
if (a[i] != b[i]) {
sum[i][m[a[i]]][m[b[i]]]++;
}
if (i > 0) {
for (int j = 0; j < 3; j++) {
for (int k = 0; k < 3; k++) {
sum[i][j][k] += sum[i - 1][j][k];
}
}
}
}
}
Data GetRange(int x, int y) {
if (x > 0) return sum[y] - sum[x - 1];
return sum[y];
}
int get_distance(int x, int y) {
Data now = GetRange(x, y);
int res = 0;
for (int i = 0; i < 3; i++) {
for (int j = i + 1; j < 3; j++) {
int min_val = min(now[i][j], now[j][i]);
res += min_val;
now[i][j] -= min_val;
now[j][i] -= min_val;
}
}
bool all_zero = true;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
all_zero &= (now[i][j] == 0);
}
}
if (all_zero) return res;
if (now[0][1] != 0 && now[0][1] == now[1][2] && now[1][2] == now[2][0]) {
res += now[0][1] * 2;
return res;
}
if (now[0][2] != 0 && now[0][2] == now[2][1] && now[2][1] == now[1][0]) {
res += now[0][2] * 2;
return res;
}
return -1;
}
