#include <bits/stdc++.h>
using namespace std;
inline void fast() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
//void ans(int n, int k) {
//// 1 3 5 7 9 11 , 2 4 6 8 10
//// 1 3 5 7 9 , 2 4 6 8 10
//
// vector<int> odd;
// vector<int> even;
//
// if(n%2==0) {
// if (k<=(n/2)){
// for(int i=1; i<=n; i+=2) {
// odd.push_back(i);
// }
// cout << odd[k-1] << endl;
// }
// else {
// for(int i=2; i<=n; i+=2) {
// even.push_back(i);
// }
// k-=(n/2);
// cout << even[k-1] << endl;
// }
// }
// else {
// if (k<=((n/2)+1)){
// for(int i=1; i<=n; i+=2) {
// odd.push_back(i);
// }
// cout << odd[k-1] << endl;
// }
// else {
// for(int i=2; i<=n; i+=2) {
// even.push_back(i);
// }
// k-=((n/2)+1);
// cout << even[k-1] << endl;
// }
// }
//}
int main() {
fast();
long long n, k; cin >> n >> k;
//odd=(2*k)-1, even=2*k;
if(n%2==0) {
if (k<=(n/2)){
cout << (2*k)-1 << endl;
}
else {
k-=(n/2);
cout << 2*k << endl;
}
}
else {
if (k<=((n/2)+1)){
cout << (2*k)-1 << endl;
}
else {
k-=((n/2)+1);
cout << 2*k << endl;
}
}
//ans(n, k);
return 0;
}
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