704.py

import re
import collections
import itertools
import heapq
import bisect


class Solution:
    def search(self, nums: List[int], target: int) -> int:

        left, right = 0, len(nums) - 1

        while left <= right:
            mid = (left + right) // 2

            if nums[mid] < target:
                left = mid + 1
            elif nums[mid] > target:
                right = mid - 1
            else:
                return mid

        return -1


class Solution2:
    def search(self, nums: List[int], target: int) -> int:

        def binary_search(left, right):
            if left <= right:

                mid = (left + right) // 2

                if nums[mid] < target:
                    return binary_search(mid+1, right)
                elif nums[mid] > target:
                    return binary_search(left, mid-1)
                else:
                    return mid
            else:
                return -1

        return binary_search(0, len(nums) - 1)


class Solution3:
    def search(self, nums: List[int], target: int) -> int:

        index = bisect.bisect_left(nums, target)

        if index < len(nums) and nums[index] == target:
            return index
        else:
            return -1