POCRI - Power Crisis

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During the power crisis in New Zealand this winter (caused by a shortage of rain and hence low levels in the hydro dams), a contingency scheme was developed to turn off the power to areas of the country in a systematic, totally fair, manner. The country was divided up into N regions (Auckland was region number 1, and Wellington number 13). A number, m, would be picked 'at random', and the power would first be turned off in region 1 (clearly the fairest starting point) and then in every m'th region after that, wrapping around to 1 after N, and ignoring regions already turned off. For example, if N = 17 and m = 5, power would be turned off to the regions in the order:1, 6, 11, 16, 5, 12, 2, 9, 17, 10, 4, 15, 14, 3, 8, 13, 7.

The problem is that it is clearly fairest to turn off Wellington last (after all, that is where the Electricity headquarters are), so for a given N, the 'random' number m needs to be carefully chosen so that region 13 is the last region selected.

Write a program that will read in the number of regions and then determine the smallest number m that will ensure that Wellington (region 13) can function while the rest of the country is blacked out.

Input

Input will consist of a series of lines, each line containing the number of regions (N) with 13 <= N < 100. The file will be terminated by a line consisting of a single 0.

Output

Output will consist of a series of lines, one for each line of the input. Each line will consist of the number m according to the above scheme.

Example

Input:
17
0

Output:
7

hide comments
bashrc is back: 2011-05-28 05:25:18

Not another one,:(Agree with dream boy.There appears no o/p file at all.I submitted a bash script with just exit 0 and AC????

hendrik: 2011-05-24 12:26:24

Agree with Egor. Without precalc my PYTH solution runs in 0.02.

Michael T: 2011-05-21 18:30:03

Don't count on "each line" in input.

cegprakash: 2011-05-19 12:49:25

i understood until 1,6,11,16,5,12,2,9,17 this.. how 10 comes next?

bashrc is back: 2011-05-19 06:32:11

Josephus to rescue..;-).So obvious if you get the logic..

meiji: 2011-05-19 05:28:56

Input terminated by EOF!

Josephus is no longer in danger.

Last edit: 2011-05-19 11:53:18
Egor: 2011-05-18 20:48:30

in my humble opinion there are weak testcases

Andreasyan: 2011-05-18 17:29:18

UVA 151

A. Muh. Primabudi: 2011-05-17 20:23:11

@johannes,thanks!!i scan until EOF and got AC

Johannes Laire: 2011-05-17 19:56:44

It seems that the terminating 0 is missing from the input, so you should also check that scanf() succeeded.


Added by:Andres Tellez
Date:2011-05-17
Time limit:3.381s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64