#include <iostream>
using namespace std;
int main() {
long long n , k ;
cin >> n;
cin >> k;
if(n % 2 == 0){
if(k <= (n / 2)){
k = (k * 2) - 1;
cout<< k;
}else{
k = ((k - (n / 2)) * 2);
cout<< k;
}
}else{
n = n + 1;
if(k <= (n / 2)){
k = (k * 2) - 1;
cout<< k;
}else{
k = ((k - (n / 2)) * 2);
cout<< k;
}
}
return 0;
}
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