# Write a NumPy program to add a border (filled with 0's) around an existing array.  
import numpy as np
x = np.ones((3,3))
print("Original array:")
print(x)
print("0 on the border and 1 inside in the array")
x = np.pad(x, pad_width=1, mode='constant', constant_values=0)
print(x)
