Rating:
# TJCTF – Gym
* **Category:** reversing
* **Points:** 20
## Challenge
> Aneesh wants to acquire a summer bod for beach week, but time is running out. Can you help him create a plan to attain his goal?
> Attachment :
> > binary
> >
> > nc p1.tjctf.org 8008
## Solution
when we run the binary we see its a gym simulation:
![screenshot](https://github.com/0d12245589/CTF-writeups/raw/master/2020/TJCTF/reversing/gym/images/screenshot1.png)
so we see that we have to reach a 180 from 211 thats 31 lbs down
lets disassemble the main function to see what does what :
![screenshot](https://github.com/0d12245589/CTF-writeups/raw/master/2020/TJCTF/reversing/gym/images/screenshot2.png)
it seems like each activity has a certain effect on weight :
```
eat healthy : -4
do 50 push-ups : -1
go for a run : -2
sleep 8 hours : -3
```
and we can only do 8 activities
obviously we cant achieve our goal using these number
but we see that for some reason when you go for a run you also sleep for 8 hours (I guess you get tired idk)
so you get an extra `-3` for the run option
in that way we can run for 6 times and then do 50 push ups : `-4*6 -1 = -31`
so by doing only that we get our flag
```
tjctf{w3iGht_l055_i5_d1ff1CuLt}
```