#include<bits/stdc++.h>
#include "dna.h"
using namespace std;
int n, q;
string a, b;
void init(string A, string B){
a=A;
b=B;
}
int get_distance(int x, int y){
int dist = y-x+1;
string s1="", s2="";
map<int, int> freq1, freq2;
for(int i = x; i<=y; i++){
s1.push_back(a[i]);
s2.push_back(b[i]);
freq1[a[i]]++;
freq2[b[i]]++;
}
string o = "ATC";
for(char c: o)
if(freq1[c]!=freq2[c])return -1;
if(y<=x+2){
int diff = 0;
for(int i=0; i<dist; i++)
if(s1[i]!=s2[i])diff++;
if(diff==2)return 1;
if(diff==0)return 0;
if(diff==1)return -1;
if(diff==3)return 2;
}
if(freq1['C']==0){
int diff = 0;
for(int i=0; i<dist; i++)
if(s1[i]!=s2[i])diff++;
return diff/2;
}
return 0;
}
