- Recursion made simple
Anybody reading data structures and algorithm would have come across a topic called “Recursion”. Now here is the best way to understand recursion. Read this ’n’ times until your understanding becomes** “True”**. Haha!! now that’s how simple the recursion is.
Well recursion can be implemented in any language and it has the same outcome. Here i’ll be demonstrating few topics and key concepts on recursion in python🐍. Yes, you read it right one love for python❤.
Introduction:
A function calling itself until a condition is set true or false is called recursive function. The below image shows to a simple function called “recursive_fun” calling itself ’n’ times.
a simple example of recursion
The output of a recursion can be understood by a concept called as tracing which is done to trace the output by a recursive function.
a tracing tree of recursive_fun(forward phase)
the above tracing tree explains a lot about how the repetitive function call takes place to obtain the desired output. Here the recursive_fun is called 3+1 times where for all the 3 times it prints ’n’ but for the last call it fails to satisfy the condition and returns 0. Hence, in any recursion the function call is made n+1 times. Also, on carefully observing the tracing tree we see that the recursive_fun executes print statement before calling itself, this is known as forward phase. A backward phase of recursion is when a function calls itself before executing any statements, i.e all the other statements are executed until there is no further function calls.
#recursive #algorithms #python #recursion #data-structures
