mathdatech/Python
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/Python.git synced 2025-02-17 14:58:10 +00:00
Code Issues Packages Projects Releases Wiki Activity

[pre-commit.ci] auto fixes from pre-commit.com hooks

Browse Source 
for more information, see https://pre-commit.ci
This commit is contained in:
pre-commit-ci[bot] 2024-10-03 09:55:24 +00:00
parent 91a43251d8
commit 66cd40e387
1 changed files with 27 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
blockchain/pow_algorithm.py
View File

@ -11,6 +11,7 @@ difficulty is defined by the number of leading zeros required in the block hash.
import hashlib import hashlib
import time import time
class Block: class Block:
def __init__(self, index, previous_hash, transactions, timestamp, difficulty): def __init__(self, index, previous_hash, transactions, timestamp, difficulty):
self.index = index self.index = index
@ -39,13 +40,16 @@ class Block:
A valid hash has the required number of leading zeros based on the difficulty A valid hash has the required number of leading zeros based on the difficulty
level. level.
""" """
target = '0' * self.difficulty # Target hash should start with 'difficulty' zeros target = (
"0" * self.difficulty
) # Target hash should start with 'difficulty' zeros
while self.hash[: self.difficulty] != target: while self.hash[: self.difficulty] != target:
self.nonce += 1 self.nonce += 1
self.hash = self.compute_hash() self.hash = self.compute_hash()
print(f"Block mined with nonce {self.nonce}, hash: {self.hash}") print(f"Block mined with nonce {self.nonce}, hash: {self.hash}")
class Blockchain: class Blockchain:
def __init__(self, difficulty): def __init__(self, difficulty):
self.chain = [] self.chain = []
@ -65,8 +69,13 @@ class Blockchain:
Adds a new block to the blockchain after performing Proof of Work. Adds a new block to the blockchain after performing Proof of Work.
""" """
previous_block = self.chain[-1] previous_block = self.chain[-1]
new_block = Block(len(self.chain), previous_block.hash, transactions, time.time(), new_block = Block(
self.difficulty) len(self.chain),
previous_block.hash,
transactions,
time.time(),
self.difficulty,
)
new_block.mine_block() new_block.mine_block()
self.chain.append(new_block) self.chain.append(new_block)
@ -89,8 +98,10 @@ class Blockchain:
return True return True
# Test cases # Test cases
def test_blockchain(): def test_blockchain():
""" """
Test cases for the Blockchain proof of work algorithm. Test cases for the Blockchain proof of work algorithm.
@ -106,11 +117,16 @@ def test_blockchain():
assert blockchain.is_chain_valid(), "Blockchain should be valid" assert blockchain.is_chain_valid(), "Blockchain should be valid"
# Tamper with the blockchain and check validation # Tamper with the blockchain and check validation
blockchain.chain[1].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering blockchain.chain[
assert not blockchain.is_chain_valid(), "Blockchain should be invalid due to tampering" 1
].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering
assert (
not blockchain.is_chain_valid()
), "Blockchain should be invalid due to tampering"
print("All test cases passed.") print("All test cases passed.")
if __name__ == "__main__": if __name__ == "__main__":
test_blockchain() test_blockchain()