Insertion sort

Soluton:

	#include <bits/stdc++.h>

	using namespace std;

	int main()
	{
	int i,j,t,n,temp;
	cout<<"Enter the array size : "<<endl;
	cin>>n;
	int a[n];
	cout<<"The unsorted array elements are: "<<endl;
	for(i=0; i<n; i++) cin>>a[i];

	for(i=1; i<n; i++)
	{
	for(j=i; j>0; j--)
	{
	if(a[j]<a[j-1])
	{
	swap(a[j],a[j-1]);
	}
	else break;
	}
	}

	cout<<"The sorted array is :"<<endl;
	for(i=0; i<n; i++)
	{
	cout<<a[i]<<endl;
	}
	return 0;
	}

view raw Insertion sort.cpp hosted with ❤ by GitHub

Bubble sort

Solution:

	#include <iostream>

	using namespace std;

	int main()
	{
	int i,j;
	int n,temp; // In case of dealing with 'char', instead of 'int', 'char' would have to be written

	cin>>n;
	int a[n];
	for(i=0;i<n;i++) cin>>a[i];
	for(i=0;i<n-1;i++)
	{
	for(j=i+1;j<n;j++)
	{
	if(a[i]>a[j])
	{
	temp=a[i];
	a[i]=a[j];
	a[j]=temp;
	}
	}
	}
	for(i=0;i<n;i++) cout<<a[i]<<endl;

	return 0;
	}

view raw Bubble sort.cpp hosted with ❤ by GitHub

Note: I have used pivot as the middle element each time.

	#include <iostream>

	using namespace std;

	void quicksort(int a[],int left, int right)
	{
	int i,j,temp,pivot;
	i=left;
	j=right;
	pivot=a[(left+right)/2];
	while(i<=j)
	{
	//For left side
	while(a[i]<pivot) i++;
	//For right side
	while(a[j]>pivot) j--;
	// a[i], which is greater than the pivot and a[j], which is less than the pivot, those two are swapping,
	// to make the all the elements left of the pivot, smaller than the pivot and right of the pivot, greater than the pivot
	if(i<=j)
	{
	swap(a[i],a[j]);
	/* Since after the swap, a[i] is smaller than the pivot & a[j] is greater than the pivot,
	so there is no need to start checking from i or j, that's why i++ and j-- is done */
	i++;
	j--;
	}
	}
	// After this loop, the left side of the present pivot is smaller and the right side is greater.
	// Now it's turn to quick sort the left and the right part
	if(left<j)
	{
	quicksort(a,left,j);
	}
	if(right>i)
	{
	quicksort(a,i,right);
	}
	}

	int main()
	{
	int n,l;
	cout<<"Enter the size of the array : "<<endl;
	cin>>n;
	int ar[n];
	cout<<"Enter the unsorted array elements : "<<endl;
	for(l=0;l<n;l++) cin>>ar[l];
	quicksort(ar,0,n-1);
	cout<<"The sorted array : "<<endl;
	for(l=0;l<n;l++)
	{
	cout<<ar[l]<<endl;
	}
	return 0;
	}

view raw Quick sort.cpp hosted with ❤ by GitHub