MInimum positive element

#include <bits/stdc++.h> 
int firstMissing(int a[], int n)
{
    // Write your code here.
    vector <int> arr ; 
    for(int i = 0 ; i < n ; i++)
    {
        arr.push_back(a[i]) ;
    }
    int min = INT_MAX ; 
    int max = INT_MIN  ;  
    for(int i = 0 ; i < n ; i++)
    {
        if(arr[i] <= 0)
        {
            continue ; 
        }
        else
        {
            if(arr[i] < min)
            {
                min = arr[i] ;
            }
            if(arr[i] > max)
            {
                max = arr[i] ;
            }
        }
         
    }
   // cout << max << min << endl ; 
    if(min > 1)
    {
       // cout << " hey" << endl ; 
        return 1 ; 
    }
    sort(arr.begin(),arr.end()) ;
    for(int i = 1; i  < max ; i++)
    {
       
        int x = 1  ; 
     
        if(binary_search(arr.begin() , arr.end() , i ) )
        {
            continue ; 
        }
        else
        {
            return i ; 
        }
    }
    
    return max + 1 ; 
    
}