# Write a NumPy program to get the block-sum (block size is 5x5) from a given array of shape 25x25.  
 import numpy as np
arra1 = np.ones((25,25))
k = 5
print("Original arrays:")
print(arra1)
result = np.add.reduceat(np.add.reduceat(arra1, np.arange(0, arra1.shape[0], k), axis=0),
                                      np.arange(0, arra1.shape[1], k), axis=1)
print("\nBlock-sum (5x5) of the said array:")
print(result)
