#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
const int MAX = 1e5 + 5;
array<array<int, 3>, 3> tree[4 * MAX];
vector<int> v1, v2;
int n;
array<array<int, 3>, 3> combine(array<array<int, 3>, 3> a, array<array<int, 3>, 3> b){
array<array<int, 3>, 3> c;
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
c[i][j] = a[i][j] + b[i][j];
}
}
return c;
}
void build(int node, int l, int r){
if(l == r) {
tree[node][v1[l]][v2[l]]++;
return;
}
int mid = (l + r) / 2;
build(2 * node, l, mid);
build(2 * node + 1, mid + 1, r);
tree[node] = combine(tree[2 * node], tree[2 * node + 1]);
}
array<array<int, 3>, 3> ask(int node, int l, int r, int ql, int qr){
if(r < ql || qr < l){
return array<array<int, 3>, 3>();
}
if(ql <= l && r <= qr){
return tree[node];
}
int mid = (l + r) / 2;
return combine(ask(2 * node, l, mid, ql, qr), ask(2 * node + 1, mid + 1, r, ql, qr));
}
map<char, int> mp = {{'A', 0}, {'T', 1}, {'C', 2}};
void init(string a, string b) {
n = a.size();
for (int i = 0; i < n; i++)
{
v1.push_back(mp[a[i]]);
}
for (int i = 0; i < n; i++)
{
v2.push_back(mp[b[i]]);
}
build(1, 0, n - 1);
}
int get_distance(int x, int y) {
array<array<int, 3>, 3> a = ask(1, 0, n - 1, x, y);
int letters[3];
memset(letters, 0, sizeof(letters));
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
letters[i] += a[i][j];
letters[j] -= a[i][j];
}
}
for (int i = 0; i < 3; i++)
{
if(letters[i] != 0) {
return -1;
}
}
int p = min(a[0][1], a[1][0]) + min(a[1][2], a[2][1]) + min(a[0][2], a[2][0]);
int s = a[0][0] + a[1][1] + a[2][2];
int t = (y - x + 1) - p * 2 - s;
return p + (t / 3 * 2);
}
