704. 二分查找

为保证权益，题目请参考 704. 二分查找(From LeetCode).

解决方案1

CPP

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

class Solution
{
public:
    int search(vector<int> &nums, int target)
    {
        if (nums.size() == 0 || target < nums[0] || target > nums[nums.size() - 1])
        {
            return -1;
        }

        int left = 0;
        int right = nums.size() - 1;
        int m = (left + right) / 2;
        while (left <= right)
        {
            m = (left + right) / 2;
            if (nums[m] < target)
            {
                left = m + 1;
            }
            else if (nums[m] > target)
            {
                right = m - 1;
            }
            else
            {
                return m;
            }
        }
        return -1;
    }
};

int main()
{
    return 0;
}

Python

# 704. 二分查找
# https://leetcode-cn.com/problems/binary-search/

################################################################################

# from typing import List
# import bisect


# class Solution:
#     def search(self, nums: List[int], target: int) -> int:
#         t = bisect.bisect_left(nums, target)
#         if t >= len(nums) or t < 0 or nums[t] != target:
#             return -1
#         return t


################################################################################

from typing import List


class Solution:
    def search(self, nums: List[int], target: int) -> int:
        l = 0
        r = len(nums) - 1
        while l <= r:
            m = (l + r) // 2
            if nums[m] == target:
                return m
            elif nums[m] > target:
                r = m - 1
            else:
                l = m + 1

        return -1


################################################################################


if __name__ == "__main__":
    solution = Solution()