How to Solve First Missing Positive Problem
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First Missing Positive
Given an unsorted integer array nums. Return the smallest positive integer that is not present in nums. You must implement an algorithm that runs in O(n) time and uses O(1) auxiliary space.
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Understanding the First Missing Positive Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
Given an unsorted integer array nums. Return the smallest positive integer that is not present in nums. You must implement an algorithm that runs in O(n) time and uses O(1) auxiliary space.
First Missing Positive
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Get real-time assistance for First Missing Positive problems during coding interviews. Interview Coder provides instant solutions and explanations.
Examples
nums = [1,2,0]3The numbers in the range [1,2] are all in the array.
nums = [3,4,-1,1]21 is in the array but 2 is missing.
nums = [7,8,9,11,12]1The smallest positive integer 1 is missing.
Constraints
1 <= nums.length <= 105231 <= nums[i] <= 231 - 1How Interview Coder Helps with Leetcode Problems
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Frequently Asked Questions
Common questions about solving First Missing Positive and using Interview Coder during coding interviews.
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