318A

#include <stdio.h>

int main()
{
	long long n, k;
	scanf("%I64d%I64d", &n, &k);
	long long even;
	if(n%2==0)
		even=n/2;
	else
		even=(n/2)+1;
	if(k<=even)
		printf("%I64d\n", 2*k-1);
	else
		printf("%I64d\n", 2*(k-even));
	return 0;
}