Python program to find power of a number using recursion

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Given a number N and power P. The task is to write a Python program to find the power of a number using recursion.

Definition: The power of a number can be defined as multiplication of the number repetitively the number of times of its power.

Example: 

Input: N=2 , P=3

Output: 8

Input: N=5 , P=2

Output: 25

Approach: The idea is to calculate power of a number ‘N’ is to multiply that number ‘P’ times i.e In first example N=2 and P=3, we are getting the result by multiplying 2 three times repetitively which gives us output 8.

Below is the implementation:

Python

def power[N, P]:

    if P == 0: 

        return 1

    return [N*power[N, P-1]] 

N = 5

P = 0

print[power[N, P]]

This is a Python Program to find the power of a number using recursion.

Problem Description

The program takes a base and a power and finds the power of the base using recursion.

Problem Solution

1. Take the base and exponential value from the user.
2. Pass the numbers as arguments to a recursive function to find the power of the number.
3. Give the base condition that if the exponential power is equal to 1, return the base number.
4. If the exponential power isn’t equal to 1, return the base number multiplied with the power function called recursively with the arguments as the base and power minus 1.
5. Print the final result.
6. Exit.

Program/Source Code

Here is source code of the Python Program to find the power of a number using recursion. The program output is also shown below.

def power[base,exp]:
    if[exp==1]:
        return[base]
    if[exp!=1]:
        return[base*power[base,exp-1]]
base=int[input["Enter base: "]]
exp=int[input["Enter exponential value: "]]
print["Result:",power[base,exp]]

Program Explanation

1. User must enter the base and exponential value.
2. The numbers are passed as arguments to a recursive function to find the power of the number.
3. The base condition is given that if the exponential power is equal to 1, the base number is returned.
4. If the exponential power isn’t equal to 1, the base number multiplied with the power function is called recursively with the arguments as the base and power minus 1.
5. The final result is printed.

Runtime Test Cases

 
Case 1:
Enter base: 2
Enter exponential value: 5
Result: 32
 
Case 2:
Enter base: 5
Enter exponential value: 3
Result: 125

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