Sorting is the rearrangement of elements in into a specific order. Sorting algorithms helps in making the solution easier and efficient. Some basic yet important sort algorithms, that one must know are as follows:

1. Selection Sort: It sorts an array by repeatedly finding the minimum element (considering decresing order) from unsorted part and putting it at the beginning.

void selection_sort(vector <int> arr, int n){
	int min_index=i;
	for(int j=i;j<n;j++){
		if(arr[j]<arr[min_index])
			min_index=j;
		}
		swap(arr[i],arr[min_index]);
	}

2. Bubble Sort: It works by repeatedly swapping the adjacent wrong elements.

void bubble_sort(vector <int> arr, int n){
	for(int itr=1;itr<n;itr++){
		for(int j=0;j<(n-itr-);j++){
			if(arr[j]>arr[j+1])
				swap(arr[j],arr[j+1]);
		}
	}
}

Recursive Bubble Sort:

void bubble_sort(vector <int> arr, int n){
    if (n == 1)        // Base case
        return;

    for (int i=0; i<n-1; i++)
        if (arr[i] > arr[i+1])
            swap(arr[i], arr[i+1]);

    bubble_sort(arr, n-1);
}

3. Insertion Sort: Values from unsorted part is picked and placed at the sorted position.

void insertion_sort(vector <int> arr, int n){
	for(int i=1;j<n;j++){
		int e=arr[i];
		int j=i-1;
		while(j>=0 && arr[j]<arr[j]>e){
			a[j+1]=a[j];
			j=j-1;
		}
		a[j+1]=e;
	}

4. Shell Sort: It is the variation of Insertion sort, as here the elements are moved far ahead.