704. Binary Search
Category: /leetcodeGiven a sorted (in ascending order) integer array nums of n elements and a target value, write a function to search target in nums. If target exists, then return its index, otherwise return -1.
Example 1:
Input: nums = [-1,0,3,5,9,12], target = 9
Output: 4
Explanation: 9 exists in nums and its index is 4
Solution:
- Binary search template
def search(self, nums: List[int], target: int) -> int:
if not nums: return -1
l, r = 0, len(nums) - 1
while l <= r:
m = (l + r) // 2
if nums[m] == target:
return m
elif nums[m] < target:
l = m + 1
else:
r = m - 1
return -1
