#0260

Find First and Last Position

MediumDSA28 min20 XP

Problem

Given sorted nums and target, return [first_index, last_index]. If target is missing, return [-1, -1].

Why This Matters

Boundary binary search is the difference between knowing binary search roughly and using it safely in production code.

Function Signature

def search_range(nums, target):

Examples

Example 1

Inputnums = [5,7,7,8,8,10], target = 8

Output[3, 4]

8 appears from index 3 through index 4.

Constraints

Return the exact requested value.
Handle edge cases cleanly.
Use the intended DSA pattern when brute force would scale poorly.

CodePython

def search_range(nums, target):
    """
    Input example: nums = [5,7,7,8,8,10], target = 8
    Return: [3, 4]
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return [-1, -1]

def search_range(nums, target):
    """
    Input example: nums = [5,7,7,8,8,10], target = 8
    Return: [3, 4]
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return [-1, -1]

Visible browser tests run here when available.

Testcases2 visible / 3 hidden categories

Repeated target

Input[5,7,7,8,8,10], target = 8

Expected[3, 4]

The lower bound of 8 is 3; the lower bound of 9 is 5.

Missing target

Input[5,7,7,8,8,10], target = 6

Expected[-1, -1]

6 is not found.

Hidden Test Categories

all values equal targettarget at beginningempty array