Program to differentiate the given Polynomial

Given polynomial string str, the task is to differentiate the given string and print the string after differentiating it. 
Note: The input format is such that there is a white space between a term and the ‘+’, ’-’ symbol
Examples: 

Input: str = "4X³ + 3X¹ + 2X²" 
Output: "12X² + 3X⁰ + 4X¹" 
Explanation: 
The derivative of p(x) = A*X^N is p'(x) = A * N * X^{N - 1}
Input: str = "5X⁴ + 6X² + 5X²" 
Output: "20X³ + 12X¹ + 10X¹"  

Approach: The idea is to observe that when the given equation consists of multiple polynomials 

, the differentiation of the given polynomial 

. And, it is known that the derivative of 

is 

Therefore, we split the given string and differentiate every term in it. 
Below is the implementation of the above approach:
 

20X^3 + 12X^1 + 10X^1