Binary Search - Rotated Array

# BINARY SEARCH

def search(nums, target, l, r):

    while l <= r: # Avoiding redundant checks by saying l <= r

        mid = int (l + (r - l) /2)

        if nums[mid] == target:
            return mid

        elif nums[mid] < target:
            l = mid + 1
           
        elif nums[mid] > target:
            r = mid - 1
    return (-1)    
      
        
numsarr = [5,7,9,15,16,19,20]      
targetnum = 5

print(search(numsarr, targetnum, l = 0, r = 6))


    # How many times an algorithm runs given the number of elements in a list = Big O notation
    # Algorithm Design - computer science is a field where its practictioners design effective algorithms to solve problems
    # Algorithms don't happen without proper ways to store and design data
    # Algorithms need data structures - binary search doesn't happen without the list being already structured in an ascending sorted way


# SORTED ARRAY BINARY SEARCH

arr = [3,4,5,6,7,0,1,2]
    # Rotated sorted array (nearly sorted)
    # Subarray A = [3,4,5,6,7] - sorted, Subarray B =  [0,1,2,3] - sorted
    # Target = 0 , RB = 3, LB = 2


def searchnew(nums, target, l, r):

    while l <= r: # Avoiding redundant checks by saying l <= r

        mid = (l + (r - l) // 2)

        if nums[mid] == target:
            return mid

        # If left bound < middle
        elif nums[l] <= nums[mid]:
            
            # If the target > middle, or target < left bound
            if target > nums[mid] or target < nums[l]:
                l = mid + 1
            
            #If the target !> middle or target !> left bound
            else: 
                r = mid - 1 
           
        # If left bound > middle
        else:

            # If the target < middle or target > right bound
            if target < nums[mid] or target > nums[r]:
                r = mid - 1

            # If the target !< middle or the target !> right
            else:
                l = mid + 1
    return (-1)    
      

print(searchnew(arr, target = 5, l = 0, r = 7))