找到数字的平方根的算法？

def binary_search(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

def newton_method(x0, tol=1e-6, max_iter=1000):
    for _ in range(max_iter):
        x1 = x0 - (x0**2 - target) / (2 * x0)
        if abs(x1 - x0) < tol:
            return x1
        x0 = x1
    return x0