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Binary search algorithm

Nov 19, 2022CodeCatch
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Topological sort

Nov 19, 2022CodeCatch

0 likes • 3 views

#Python program to print topological sorting of a DAG
from collections import defaultdict
#Class to represent a graph
class Graph:
def __init__(self,vertices):
self.graph = defaultdict(list) #dictionary containing adjacency List
self.V = vertices #No. of vertices
# function to add an edge to graph
def addEdge(self,u,v):
self.graph[u].append(v)
# A recursive function used by topologicalSort
def topologicalSortUtil(self,v,visited,stack):
# Mark the current node as visited.
visited[v] = True
# Recur for all the vertices adjacent to this vertex
for i in self.graph[v]:
if visited[i] == False:
self.topologicalSortUtil(i,visited,stack)
# Push current vertex to stack which stores result
stack.insert(0,v)
# The function to do Topological Sort. It uses recursive
# topologicalSortUtil()
def topologicalSort(self):
# Mark all the vertices as not visited
visited = [False]*self.V
stack =[]
# Call the recursive helper function to store Topological
# Sort starting from all vertices one by one
for i in range(self.V):
if visited[i] == False:
self.topologicalSortUtil(i,visited,stack)
# Print contents of stack
print(stack)
g= Graph(6)
g.addEdge(5, 2);
g.addEdge(5, 0);
g.addEdge(4, 0);
g.addEdge(4, 1);
g.addEdge(2, 3);
g.addEdge(3, 1);
print("Following is a Topological Sort of the given graph")
g.topologicalSort()

Caesar Encryption

Mar 10, 2021Skrome

0 likes • 1 view

import string
def caesar(text, shift, alphabets):
def shift_alphabet(alphabet):
return alphabet[shift:] + alphabet[:shift]
shifted_alphabets = tuple(map(shift_alphabet, alphabets))
final_alphabet = "".join(alphabets)
final_shifted_alphabet = "".join(shifted_alphabets)
table = str.maketrans(final_alphabet, final_shifted_alphabet)
return text.translate(table)
plain_text = "Hey Skrome, welcome to CodeCatch"
print(caesar(plain_text, 8, [string.ascii_lowercase, string.ascii_uppercase, string.punctuation]))

collect dictionary

Nov 19, 2022CodeCatch

0 likes • 1 view

from collections import defaultdict
def collect_dictionary(obj):
inv_obj = defaultdict(list)
for key, value in obj.items():
inv_obj[value].append(key)
return dict(inv_obj)
ages = {
'Peter': 10,
'Isabel': 10,
'Anna': 9,
}
collect_dictionary(ages) # { 10: ['Peter', 'Isabel'], 9: ['Anna'] }

Hello, python

Jan 20, 2021Ntindle

0 likes • 4 views

print(“Hello World”)

Bubble sort

Nov 19, 2022CodeCatch

0 likes • 3 views

# Python program for implementation of Bubble Sort
def bubbleSort(arr):
n = len(arr)
# Traverse through all array elements
for i in range(n-1):
# range(n) also work but outer loop will repeat one time more than needed.
# Last i elements are already in place
for j in range(0, n-i-1):
# traverse the array from 0 to n-i-1
# Swap if the element found is greater
# than the next element
if arr[j] > arr[j+1] :
arr[j], arr[j+1] = arr[j+1], arr[j]
# Driver code to test above
arr = [64, 34, 25, 12, 22, 11, 90]
bubbleSort(arr)
print ("Sorted array is:")
for i in range(len(arr)):
print ("%d" %arr[i]),

Create a Pascal’s Triangle

May 31, 2023CodeCatch

0 likes • 1 view

def generate_pascals_triangle(num_rows):
triangle = []
for row in range(num_rows):
# Initialize the row with 1
current_row = [1]
# Calculate the values for the current row
if row > 0:
previous_row = triangle[row - 1]
for i in range(len(previous_row) - 1):
current_row.append(previous_row[i] + previous_row[i + 1])
# Append 1 at the end of the row
current_row.append(1)
# Add the current row to the triangle
triangle.append(current_row)
return triangle
def display_pascals_triangle(triangle):
for row in triangle:
for number in row:
print(number, end=" ")
print()
# Prompt the user for the number of rows
num_rows = int(input("Enter the number of rows for Pascal's Triangle: "))
# Generate Pascal's Triangle
pascals_triangle = generate_pascals_triangle(num_rows)
# Display Pascal's Triangle
display_pascals_triangle(pascals_triangle)