Standard Template Library – Algorithm

               Algorithms are predefined function to perform a specific functionality. In STL, the built-in header files are <algorithm> and <numeric>.

Algorithms can be classified into 4 types based on its functionality.

• 1.      Sorting algorithms
• 2.      Searching algorithms.
• 3.      Manipulation algorithm
• 4.      Counting and comparing algorithm

 Let us discuss about the algorithm in each category.

1.   Sorting algorithms:

This is the algorithm which arranges the element in particular order. The functions are given below.

    “sort()” : it arranges the elements in particular order.

    “nth_element()” : it rearranges the element based on the ‘n’ value.

    “is_sorted()”: it checks the given array is sorted or not.

    “is_sorted_until()”: it returns the first element where the sorted order breaks.

    “stable_sort()”: it sorts the elements and also preserves the relative order.

    “partial_sort()”:it sorts the first n elements in particular order.

2.Searching algorithms:

              It searches the particular element in the given array. it has lot of built-in functions as follows.

‘binary_search()’: sorts based on binary search algorithm.

‘lower_bound()’: it gives the lower bound value.

‘upper_bound()’: it gives the upper bound value.

‘find()’: searches an element and gives the element is present or not.

‘find_if()’ : it finds the first data which satisfies the condition.

‘find_end()’: it finds the last element of the data structures.

‘count()”: it gives you the number of elements.

‘count_if()’: it gives you the count within the range.

3.Manipulation Algorithms

              This algorithm handles the operations on the data elements. The functions are given below.

‘fill()’ : it fills the same data in all elements.

‘copy()’ : it copies the element in the range.

‘copy_if()’ : it copies the element if the condition met.

‘copy_n()’: it copies the n elements in the range.

‘copy_backward()’: it copies the data in the backward.

‘move()’: move a set of values to particular range.

‘swap()’ :it exchanges the value.

‘replace()’: replace a specific value.

‘replace_if()’ :replace a value when it met a condition.

‘remove()” : it deletes the data.

‘transform()’: it makes the data range with another value.

‘generate()’: it generates the value.

‘shuffle()’: it rearranges the data randomly.

4. Counting and comparing algorithm

If you want to find the number of elements and want to compare the data, these are the functions you need to know.

‘count’: it returns the number of elements.

‘count_if’: it returns the number of elements in particular range.

Comparing algorithms:

‘mismatch()’:  it finds the position from which the range differs.

‘equal()’ : it checks for two ranges for order and its element.

‘lexicographical_compare()’: The comparison is based on the dictionary order.

‘is_permutation() : it checks for permutation order in the elements.

These are the various types of algorithm functions in Standard Template Library. Hope, this blog post is useful to you.