BISHOPS  Bishops
Yesterday was Sam's birthday. The most interesting gift was definitely the chessboard. Sam quickly learned the rules of chess and defeated his father, all his friends, his little sister, and now no one wants to play with him any more.
So he decided to play with another birthday gift – a Book of Math Problems for Young Mathematicians. He opened the book somewhere in the middle and read the following problem: "How many knights can be placed on a chessboard without threatening each other?" After a while he realized that this was trivial and moved on to the next problem: "How many bishops can be placed on a chessboard without threatening each other?". Sam is in trouble here. He is not able to solve this problem and needs your help.
Sam's chessboard has size N x N. A bishop can move to any distance in any of the four diagonal directions. A bishop threatens another bishop if it can move to the other bishop's position. Your task is to compute the maximum number of bishops that can be placed on a chessboard in such a way that no two bishops threaten each other.
Input
The input file consists of several lines. The line number i contains a single positive integer N representing the size of the ith chessboard. [1 <= N <= 10^100]
Output
The output file should contain the same number of lines as the input file. The ith line should contain one number – the maximum number of bishops that can be placed on ith chessboard without threatening each other.
Example
Input: 2 3 Output: 2 4
hide comments
harshit sharma:
20170404 09:34:47
@sushant you have to give answer n fixed format i.e you have to print 100000 not 1e+5 

sushantgokhale:
20170404 09:24:32
tried it even using string but still its showing WA : 

sushantgokhale:
20170404 09:15:29
@harshit sharma. In long double, its not overflowing. Confirmed it. 10^100 is shown as 1e+100. But if converted to fixed point format in c++, it shown as 100000000678787896365... . Dont know why this is being rounded. 

harshit sharma:
20170404 08:23:14
your value might be overflowing @sushant 

sushantgokhale:
20170404 06:07:14
does it require output in form of fixed point floating format or scientific format will also do? If I convert to fixed point, getting lot of round off. Any suggestions? 

Simran Saha:
20170403 07:58:05
can anybody provide some more test cases?


ameyanator:
20170319 22:32:56
barely 34 lines of logic. If you're using java then use hasNextBigInteger() available in scanner class. 

vanvinhbk94:
20170219 04:57:07
use c++,


nilabja16180:
20170215 21:24:45
With python AC in One Go


scorpion_ajay:
20170116 09:12:45
just get the pattern, rest is easy

Added by:  Roman Sol 
Date:  20050417 
Time limit:  1s 
Source limit:  10000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  IPSC 2004 