Difference between In-place and Out-of place algorithm

Here we will learn about the difference between the In-place algorithm and Out-of place algorithm

features	In-place algorithm	Out-of place algorithm
1. Example	Bubble sort, comb sort, Selection sort, Insertion sort, heap sort, shell sort standard standard standard standard standard	The standard merge sort algorithm
2. Time Complexity	o(log n)	o(n)
3. Requirements	It requires only a few pointers. That’s why it reduces the time complexity	This algorithm requires extra space for merging. thus, it increases time complexity.

 

 

In-place algorithm

1. In the In-place algorithm, we do not require any extra memory allocation. As soon as our algorithm executes output simply overwrite the input. Thus, It saves additional memory consumption.
2. In the In-place algorithm, memory requirements for the output are independent of input size and should be constant.
3. In-place algorithm used in systems that runs limited memory like embedded systems. It reduces memory usage to a large extent. But also it has high time complexity.
4. It counts everything in the algorithm including function calls, pointer, etc.
5. It writes output in write-only memory, so it’s become more appropriate to consider only the working part of the algorithm.

Diagram for In-place algorithm

In the in-place Sorting algorithm we don’t need extra memory or indexes for sorting. This algorithm sorts the elements between them by exchanging their locations. this is how this algorithm reduces the time complexity as well as space complexity.

In step 1, It interchanges the elements between positions 1 and 5.

In step 2, interchanges the elements between positions 2 and 4 and stores it in the memory.

Out-of Place algorithm

1. Out-of Place algorithm is Opposite to the In-place algorithm, it is also called an Out-in-place algorithm.
2. Its output depends on input size.
3. merge-sort algorithm is an example of an out-of-place algorithm. It requires extra space for merging and also increases time complexity.

Diagram for Out-of-place algorithm

In the out-of-place algorithm, it needs extra space to sort the elements. As shown in figures.

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Step 1:

As we can see, for sorting element number five it created a new location for the element and placed it at the beginning of the list.

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Step 2:

For element number four it allocated a new location in the memory and place it next to element number five.

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Step 3:

Similarly, for element number three it allocated a new space at the memory and placed that element next to the fourth one.

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Step 4:

For element number two, it also worked the same as above i.e. it created a new location and placed it next to the third one.

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Step 5:

Also for element number one, it allocated a new memory location at the place near its corresponding one.

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This is how the Out-of-place algorithm works and not only increases time complexity but also space complexity.

Program for Reverse the number in C++

#include<iostream.h> //these are input output stream header which access input output library files 
#include<conio.h> //this library file access getch method in this porgram.
using namespace std;
class Reverse //creating a class
{
    int a, rev=0, rem; //creating a variables with datatype integer
    cout<<"Enter a number:"; //Printing the message
    cin>>a; //getting value from users
      while(a!=0) //declaring the condition i.e the number got from user is not equal to 0
       {
         rem=a%10; //if condition will be true this loop execute
         rev=rev*10+rem;
         a/=10;
        }
    cout<<"Reversed Number is:"<<rev<<endl; //printing the reverse number with message
    getch(); //using for diaplying the output
    return 0; //returing the value
}

Output

Enter a number:856
Reversed number:658

Program for reverse number  in python

num=7856 //getting number for reverse
rev=0 
while num!=0: //applying condtion i.e number is not equal to zero
   rem=num%10 //if condition will true this while loop will execute
   rev=rev*10+rem
   num//=10
print("Reversed number:"+str(rev)) //printing the number after reverse

Output

Reversed number:6857

Program for reverse number in java

Enlightenerpublic class RevNum //creating a public class 
{
  public static void main(String args[]) 
   {
    int num=7586, rev=0;//creating a paramter in integer data type
    while(num!=0) //applying condition i.e. if number is not equal to 0
   {
    int rem=num%10; // rem is using as a varibale for remainder in integer data type
    rev=rev*10+rem; //rev is using for reverse 
    num/=10;
   }
   System.out.println("Reversed number:"+rev); //here we are printing the number after reverse
   }
}

Output

Reversed number:6857