Given an unsorted array of integers, find the smallest positive integer that is missing.

Question

Accepted Answer

Find the first missing number in an array of strings.

Convert the array of strings to an array of integers.
Sort the array of integers.
Iterate through the sorted array to find the first missing number.

Accepted Answer

import java.util.*;
class Main {
     int array2[]={-10, -3, 0, 5, 12, -7, 8};
      int minimum=100;
      for(int i:array2){
          if(i&amp;gt;0 &amp;amp;&amp;amp; i&amp;lt;minimum){
              minimum=i;
          }
      }
      int temp=minimum-1;
      if(temp&amp;gt;0){
          System.out.println("Missing positive integer is :"+ temp);
      }
      
    }
}

The code in java . Sort the array and minus 1 from the smallest +ve element

Accepted Answer

def firstMissingPositive(nums): n = len(nums) # Step 1: Remove non-positive and large values for i in range(n): if nums[i] <= 0 or nums[i] > n: nums[i] = n + 1 # Step 2: Mark presence for i in range(n): num = abs(nums[i]) if 1 <= num <= n: nums[num - 1] = -abs(nums[num - 1]) # Step 3: Find the first index with a positive value for i in range(n): if nums[i] > 0: return i + 1 return n + 1

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Given an unsorted array of integers, find the smallest positive integer that is missing.

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