Sort an array which contain 1 to n values

You have given an array which contain 1 to n element, your task is to sort this array in an efficient way and without replace with 1 to n numbers.

Examples :

Input : arr[] = {10, 7, 9, 2, 8, 
                 3, 5, 4, 6, 1};
Output : 1 2 3 4 5 6 7 8 9 10

Native approach :
Sort this array with the use of any type of sorting method. it takes O(nlogn) minimum time.



Efficient approach :
Replace every element with it’s position. it takes O(n) efficient time and give you the sorted array. Let’s understand this approach with the code below.

C++

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// Efficient C++ program to sort an array of
// numbers in range from 1 to n.
#include <bits/stdc++.h>
  
using namespace std;
  
// function for sort array
void sortit(int arr[], int n)
{
    for (int i = 0; i < n; i++) {
      arr[i]=i+1;
    }
}
  
// Driver code
int main()
{
    int arr[] = { 10, 7, 9, 2, 8, 3, 5, 4, 6, 1 };
    int n = sizeof(arr) / sizeof(arr[0]);
  
    // for sort an array
    sortit(arr, n);
  
    // for print all the element in sorted way
    for (int i = 0; i < n; i++) 
        cout << arr[i] << " ";    
}

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Java














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// Efficient Java program to sort an  


// array of numbers in range from 1 


// to n. 


import java.io.*; 


import java.util.*; 


  


public class GFG { 


      


          


    // function for sort array 


    static void sortit(int []arr, int n) 


    { 


        for (int i = 0; i < n; i++)  


        { 


            arr[i]=i+1; 


      


              


        } 


    } 


      


    // Driver code 


    public static void main(String args[]) 


    { 


        int []arr = {10, 7, 9, 2, 8,  


                            3, 5, 4, 6, 1}; 


        int n = arr.length; 


      


        // for sort an array 


        sortit(arr, n); 


      


        // for print all the  


        // element in sorted way 


        for (int i = 0; i < n; i++)  


            System.out.print(arr[i] + " ");  


    } 


} 


  


// This code is contributed by Manish Shaw  


// (manishshaw1) 



















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Python3














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# Python3 program to sort an array of  


# numbers in range from 1 to n.  


  


# function for sort array  


def sortit(arr,n): 


    for i in range(n): 


        arr[i] = i+1


  


# Driver code 


if __name__=='__main__': 


    arr = [10, 7, 9, 2, 8, 3, 5, 4, 6, 1 ] 


    n = len(arr) 


  


    # for sort an array  


    sortit(arr,n) 


  


    # for print all the element  


    # in sorted way  


    for i in range(n): 


        print(arr[i],end=" ") 


   


# This code is contributed by  


# Shrikant13  



















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C#














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// Efficient C# program to sort an array of 


// numbers in range from 1 to n. 


using System; 


using System.Collections.Generic; 


  


class GFG { 


      


          


    // function for sort array 


    static void sortit(int []arr, int n) 


    { 


        for (int i = 0; i < n; i++)  


        { 


      


            arr[i]=i+1; 


        } 


    } 


      


    // Driver code 


    public static void Main() 


    { 


        int []arr = {10, 7, 9, 2, 8,  


                      3, 5, 4, 6, 1}; 


        int n = arr.Length; 


      


        // for sort an array 


        sortit(arr, n); 


      


        // for print all the  


        // element in sorted way 


        for (int i = 0; i < n; i++)  


            Console.Write(arr[i] + " ");  


    } 


} 


  


// This code is contributed by  


// Manish Shaw (manishshaw1) 



















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PHP














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<?php 


// Efficient PHP program to sort an  


// array of numbers in range from 1 to n. 


  


  


// function for sort array 


function sortit(&$arr, $n) 


{ 


    for ($i = 0; $i < $n; $i++)  


    { 


  


        $arr[$i]=$i+1;   


    } 


} 


  


// Driver code 


$arr = array(10, 7, 9, 2, 8,  


             3, 5, 4, 6, 1); 


$n = count($arr); 


  


// for sort an array 


sortit($arr, $n); 


  


// for print all the 


// element in sorted way 


for ($i = 0; $i < $n; $i++)  


    echo $arr[$i]." "; 


  


//This code is contributed by Manish Shaw 


//(manishshaw1) 


?> 



















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Output :


1 2 3 4 5 6 7 8 9 10






          
          
          

          

    

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    Article Tags : 
Arrays
Sorting

           	
Practice Tags : 
Arrays
Sorting

        

         

         
 
         
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