Given two square matrices A and B of size n x n each, find their multiplication matrix. 
Naive Method 

Following is simple Divide and Conquer method to multiply two square matrices. 

1) Divide matrices A and B in 4 sub-matrices of size N/2 x N/2 as shown in the below diagram. 
2) Calculate following values recursively. ae + bg, af + bh, ce + dg and cf + dh.

Strassen’s Matrix Multiplication  : https://www.geeksforgeeks.org/strassens-matrix-multiplication/