Binary Search Hacks

Problem 1 Code: Basic Binary Search

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# Problem 1: Basic Binary Search

def binary_search_iterative(arr, target):
    left, right = 0, 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

# Test for Problem 1
arr1 = [1, 3, 5, 7, 9, 11, 13]
target1 = 7
result1 = binary_search_iterative(arr1, target1)
print(f"Index of {target1}: {result1}")

Index of 7: 3

Problem 2 Code: Recursive Binary Search

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# Problem 2: Recursive Binary Search

def binary_search_recursive(arr, target, left, right):
    if left > right:
        return -1
    mid = (left + right) // 2
    if arr[mid] == target:
        return mid
    elif arr[mid] < target:
        return binary_search_recursive(arr, target, mid + 1, right)
    else:
        return binary_search_recursive(arr, target, left, mid - 1)

# Test for Problem 2
arr2 = [10, 20, 30, 40, 50, 60, 70, 80]
target2 = 30
result2 = binary_search_recursive(arr2, target2, 0, len(arr2) - 1)
print(f"Index of {target2}: {result2}")

Index of 30: 2