#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
int pf[6][100005], cur[6];
char p[] = {'A', 'A', 'C', 'C', 'T', 'T'};
char q[] = {'C', 'T', 'A', 'T', 'A', 'C'};
void init(string a, string b) {
for (int k = 0; k < 6; k++) {
for (int i = 0; i < (int)a.size(); i++) {
pf[k][i] = i ? pf[k][i - 1] : 0;
if (a[i] == p[k] && b[i] == q[k]) {
pf[k][i]++;
}
}
}
}
int reduce(int &x, int &y) {
int z = min(x, y);
x -= z;
y -= z;
return z;
}
int get_distance(int x, int y) {
for (int k = 0; k < 6; k++) {
cur[k] = pf[k][y] - (x ? pf[k][x - 1] : 0);
}
int ans = 0;
ans += reduce(cur[0], cur[2]);
ans += reduce(cur[1], cur[4]);
ans += reduce(cur[3], cur[5]);
if (cur[1] != cur[5] || cur[5] != cur[2]) return -1;
if (cur[0] != cur[3] || cur[3] != cur[4]) return -1;
ans += cur[1] * 2;
ans += cur[0] * 2;
return ans;
}
