#include <cmath>
#include <iostream>
#include <utility>
#include <algorithm>
#include <cstdio>
#include <vector>
#include <string>
#include <fstream>
#include "dna.h"
using namespace std;
vector<int>aa;
vector<int>ab;
vector<int>ac;
vector<int>ba;
vector<int>bb;
vector<int>bc;
vector<int>mismo;
string j;
string g;
void init(std::string a, std::string b) {
j=a;
g=b;
int n=a.size();
aa.assign(n+1,0);
ab.assign(n+1,0);
ac.assign(n+1,0);
ba.assign(n+1,0);
bb.assign(n+1,0);
bc.assign(n+1,0);
mismo.assign(n+1,0);
for(int i=1;i<=n;i++){
mismo[i]=mismo[i-1];
if(a[i-1]==b[i-1]){
mismo[i]=mismo[i-1]+1;
}
}
for(int i=1;i<n+1;i++){
aa[i]=aa[i-1];
ab[i]=ab[i-1];
ac[i]=ac[i-1];
ba[i]=ba[i-1];
bb[i]=bb[i-1];
bc[i]=bc[i-1];
if(a[i-1]=='A')aa[i]=aa[i-1]+1;
else if(a[i-1]=='T')ab[i]=ab[i-1]+1;
else if(a[i-1]=='C')ac[i]=ac[i-1]+1;
if(b[i-1]=='A')ba[i]=ba[i-1]+1;
else if(b[i-1]=='T')bb[i]=bb[i-1]+1;
else if(b[i-1]=='C')bc[i]=bc[i-1]+1;
}
}
int get_distance(int x, int y) {
bool pos=true;
if(aa[y+1]-aa[x]!=ba[y+1]-ba[x])pos=false;
else if(ab[y+1]-ab[x]!=bb[y+1]-bb[x])pos=false;
else if (ac[y+1]-ac[x]!=bc[y+1]-bc[x])pos=false;
if(pos){
if(x==y)return 0;
if(y-x==1){
if(j[x]!=g[x])return 1;
else return 0;
}
else if(y-x==2){
int h=mismo[y+1]-mismo[x];
if(h==3)return 0;
else if(h==2 ||h==1)return 1;
else return 2;
}
else{
int l=y-x;
vector<bool>co(l,false);
int sp=0;
int p=0;
for(int i=x;i<y;i++){
if(g[i]==j[i])co[i-x]=true;
}
for(int i=x;i<y;i++){
if(!co[i-x]){
for(int k=i+1;k<y;k++){
if(g[i]==j[k] && g[k]==j[i] && !co[k-x]){
p++;
co[i-x]=true;
co[k-x]=true;
break;
}
}
if(!co[i-x])sp++;
}
}
p+=(sp/3)*2;
p+=sp%3;
return p;
}
}
if(!pos)return -1;
return 0;
}
