# Python binary search function
def binary_search(arr, target):
    left = 0
    right = len(arr) - 1
    while left <= right:
        mid = (left + right) // 2
        if arr[mid] == target:
            return mid
        elif arr[mid] < target:
            left = mid + 1
        else:
            right = mid - 1
    return -1

# Usage
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
target = 7
result = binary_search(arr, target)
if result != -1:
    print(f"Element is present at index {result}")
else:
    print("Element is not present in array")

# @return a list of strings, [s1, s2]
def letterCombinations(self, digits):
    if '' == digits: return []
    kvmaps = {
        '2': 'abc',
        '3': 'def',
        '4': 'ghi',
        '5': 'jkl',
        '6': 'mno',
        '7': 'pqrs',
        '8': 'tuv',
        '9': 'wxyz'
    }
    return reduce(lambda acc, digit: [x + y for x in acc for y in kvmaps[digit]], digits, [''])

filename = "data.txt"
data = "Hello, World!"

with open(filename, "a") as file:
    file.write(data)

# function which return reverse of a string
def isPalindrome(s):
    return s == s[::-1]
 
# Driver code
s = "malayalam"
ans = isPalindrome(s)
 
if ans:
    print("Yes")
else:
    print("No")

# Function to multiply two matrices
def multiply_matrices(matrix1, matrix2):
    # Check if the matrices can be multiplied
    if len(matrix1[0]) != len(matrix2):
        print("Error: The number of columns in the first matrix must be equal to the number of rows in the second matrix.")
        return None

    # Create the result matrix filled with zeros
    result = [[0 for _ in range(len(matrix2[0]))] for _ in range(len(matrix1))]

    # Perform matrix multiplication
    for i in range(len(matrix1)):
        for j in range(len(matrix2[0])):
            for k in range(len(matrix2)):
                result[i][j] += matrix1[i][k] * matrix2[k][j]

    return result

# Example matrices
matrix1 = [[1, 2, 3],
           [4, 5, 6],
           [7, 8, 9]]

matrix2 = [[10, 11],
           [12, 13],
           [14, 15]]

# Multiply the matrices
result_matrix = multiply_matrices(matrix1, matrix2)

# Display the result
if result_matrix is not None:
    print("Result:")
    for row in result_matrix:
        print(row)

my_list = ["blue", "red", "green"]

#1- Using sort or srted directly or with specifc keys
my_list.sort() #sorts alphabetically or in an ascending order for numeric data 
my_list = sorted(my_list, key=len) #sorts the list based on the length of the strings from shortest to longest. 
# You can use reverse=True to flip the order

#2- Using locale and functools 
import locale
from functools import cmp_to_key
my_list = sorted(my_list, key=cmp_to_key(locale.strcoll))