Python Program to Find closest number in array

# Python3 program to find element
# closest to given target.

# Returns element closest to target in arr[]


def findClosest(arr, n, target):

    # Corner cases
    if (target <= arr[0]):
        return arr[0]
    if (target >= arr[n - 1]):
        return arr[n - 1]

    # Doing binary search
    i = 0
    j = n
    mid = 0
    while (i < j):
        mid = (i + j) // 2

        if (arr[mid] == target):
            return arr[mid]

        # If target is less than array
        # element, then search in left
        if (target < arr[mid]):

            # If target is greater than previous
            # to mid, return closest of two
            if (mid > 0 and target > arr[mid - 1]):
                return getClosest(arr[mid - 1], arr[mid], target)

            # Repeat for left half
            j = mid

        # If target is greater than mid
        else:
            if (mid < n - 1 and target < arr[mid + 1]):
                return getClosest(arr[mid], arr[mid + 1], target)

            # update i
            i = mid + 1

    # Only single element left after search
    return arr[mid]


# Method to compare which one is the more close.
# We find the closest by taking the difference
# between the target and both values. It assumes
# that val2 is greater than val1 and target lies
# between these two.
def getClosest(val1, val2, target):

    if (target - val1 >= val2 - target):
        return val2
    else:
        return val1


# Driver code
arr = [1, 2, 4, 5, 6, 6, 8, 9]
n = len(arr)
target = 11
print(findClosest(arr, n, target))

# Python3 program to find element
# closest to given target.

def findClosestValue(givenList, target):

    def difference(givenList):
        return abs(givenList - target)

    result = min(givenList, key=difference)

    return result


if __name__ == "__main__":

    givenList = [1, 2, 4, 5, 6, 6, 8, 9]

    target = 11

    result = findClosestValue(givenList, target)

    print("The closest value to the " + str(target)+" is", result)
# This code is contributed by  vikkycirus

# Python program to find element
# closest to given target using two pointers
import sys
 
def findClosest(arr, n, target):
    left, right = 0, n - 1
    while left < right:
        if abs(arr[left] - target) <= abs(arr[right] - target):
            right -= 1
        else:
            left += 1
    return arr[left]
 
if __name__ == "__main__":
    arr = [1, 2, 4, 5, 6, 6, 8, 8, 9]
    n = len(arr)
    target = 11
    print(findClosest(arr, n, target))

# This code is contributed by Susobhan Akhuli