---
# System prepended metadata

title: GENERAL
tags: [CTF, CRYPTO, CRYPTOHACK]

---

# GENERAL

ENCODING
---
### ASCII
- int -> ASCII
```=python
chr(_integer_)  # ->ASCII
print(chr(97))  # 'a'
```
- ASCII -> int
```=python
ord(_ASCII_)  # ->integer
print(ord('a'))  # 97
```
### Hex
```=python
import binascii
```
- hex -> binary
```=python
binascii.unhexlify(b'0x__')  # ->binary
print(binascii.unhexlify(b'0xFFFF')) # b'307846464646'
```
- binary -> hex
```=python
binascii.hexlify(b'binary') # ->hex
print(binascii.hexlify(b'307846464646')) # b'0xFFFF'
```

### Base64
### Bytes and Big Integers
- int -> binary

### Encoding Challenge

XOR
---
### XOR Starter
### XOR Properties
### Favorite byte
### You either know, XOR you don't
### Lemur XOR

MATHMATICS
---
### Greatest Common Divisor
### Extended GCD
### Modular Arithmetic 1
### Modular Arithmetic 2
### Modular Inverting

DATA FORMATS
---
### Privacy-Enhanced Mail?
### CERTainly not
### Transparency

###### tags: `CRYPTOHACK` `CTF` `CRYPTO`
