Neoalgo: First Missing Positive Number

[smv1999]

🚀 Feature

Given an array of integers, find the first missing positive integer in linear time and constant space. In other words,
find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well.

For example, the input [3, 4, -1, 1] should give 2. The input [1, 2, 0] should give 3.

You can modify the input array in-place.

Have you read the Contributing Guidelines on Pull Requests?

Yes

Motivation

This problem helps to understand how to work with arrays "in-place" .

Pitch

This problem expects solution in Linear time (O(n)) and constant space (O(1)) which poses a challenge to come up with optimal solution. This makes this problem interesting!

Happy Coding!

Programming Language Assigned

• CPP - @smv1999
• Python - @devanshi-katyal
• C - @SangeetaMishra
• Java - @ritvij14

[smv1999]

@SKAUL05 @Abhijit2505 @HarshCasper I want to work on this issue in CPP! Kindly assign me this issue!

[devanshi-katyal]

i would like to work on this issue in python

[SangeetaMishra]

I would like to work in C.

[ritvij14]

I would like to take this in Java. for CH20

[Abhijit2505]

@smv1999 , please get started with the solution in CPP

[Abhijit2505]

@devanshi-katyal , get started with the solution in Python

[Abhijit2505]

@SangeetaMishra , please get started with the solution in C.

[Abhijit2505]

@ritvij14 please get started with the solution in Java

[SangeetaMishra]

@SangeetaMishra , please get started with the solution in C.

Solve it in C. #882 @Abhijit2505 @SKAUL05 @siddharth25pandey @iamrajiv

[HarshCasper]

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