#include<stdio.h>

int main()
{
	unsigned long long d;
	int b;
	while(scanf("%llu",&d)!=EOF)
	{
		if(d!=0)
	{
		b=d*2-1;
	}
		else{
		b=0;
		}
		printf("%llu ",b);
}
	return 0;
}
麻了，学长帮帮我