VZLA2019A - A not so good plan

On the International Conglomerate of Pest Control (ICPC) they make experiments with exactly five laboratory mice. They are numbered from 1 to 5 and they are extremely intelligent

Last night they developed a escape plan, but surprisingly only one mouse made it out of the building. Can you tell which one escaped?

Input

The first and only line contains exactly four different integers a, b, c, d, being the number of each mouse remaining on the laboratory respectively..

Output

Print the number of the mouse that escaped

Example

Input:
1 2 4 5

Output:
3

Constraints

1 ≤ a, b, c, d ≤ 5


Added by:Samuel Nacache
Date:2019-10-27
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All
Resource:Samuel Nacache - Used for Venezuelan 2019 ICPC Local Contest

hide comments
2019-11-09 03:00:04
A problem that can be solved in a number of ways, like this one, should be set up so that these ways can be compared. This is especially important for simple problems where a curious beginner might be compelled to be creative when seeing superior runtimes of other users. Unfortunately, with n=5 there is no difference between the brutest force and smarter approaches, so there is no motivation to improve. Worse still, multiple testfiles add an overhead for languages with startup time which yield pretty much random runtimes (vide my Python oneliner ACing at 0.08s).

2-3 testfiles with n < 200000 would knock out stupid solutions but provide slight difference between speeds of other concepts without making I/O too much of a factor, in C at least.
2019-11-03 17:57:28 Rocker3011
@nadstratosfer the problem was made for a local contest aimed mainly at beginners , it is natural for a experienced coder like you to see it as useless, but for a beginner it is a good way to try out the system for the first time.
2019-10-28 14:37:41
This doesn't even make sense in Basics as weak constraints and poor testfile setup won't allow comparing approaches.

Useless.
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