# Returns index of target in arr if present, else -1
def binary_search(arr, target):
	low = 0
	high = len(arr) - 1

	while low <= high:
		# Check base case
		mid = (high + low) // 2

		# If element is smaller than mid, then it can only
		# be present in left subarray
		if arr[mid] > target:
			high = mid - 1
		# Else the element can only be present in right subarray
		elif arr[mid] < target:
			low = mid + 1
		# If element is present at the middle itself
		else:
			return mid

	# Element is not present in the array
	return -1

# Test array
arr = [ 2, 3, 4, 10, 40 ]
target = 10

result = binary_search(arr, target)

if result != -1:
	print("Element is present at index", str(result))
else:
	print("Element is not present in array")

def quick_sort(arr):
    if len(arr) <= 1:
        return arr
    else:
        pivot = arr[0]
        left = [x for x in arr[1:] if x <= pivot]
        right = [x for x in arr[1:] if x > pivot]
        return quick_sort(left) + [pivot] + quick_sort(right)

# Example usage:
input_array = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]
sorted_array = quick_sort(input_array)

print("Original Array:", input_array)
print("Sorted Array:", sorted_array)

import csv

# Writing to a CSV file
with open('data.csv', 'w', newline='') as csvfile:
    fieldnames = ['name', 'age', 'city']
    writer = csv.DictWriter(csvfile, fieldnames=fieldnames)

    writer.writeheader()
    writer.writerow({'name': 'John', 'age': 30, 'city': 'New York'})
    writer.writerow({'name': 'Alice', 'age': 25, 'city': 'London'})

# Reading from a CSV file
with open('data.csv', newline='') as csvfile:
    reader = csv.DictReader(csvfile)
    for row in reader:
        print(row)