tvl-depot/users/wpcarro/scratch/data_structures_and_algorithms/array-traversals.py
Vincent Ambo 019f8fd211 subtree(users/wpcarro): docking briefcase at '24f5a642'
git-subtree-dir: users/wpcarro
git-subtree-mainline: 464bbcb15c
git-subtree-split: 24f5a642af
Change-Id: I6105b3762b79126b3488359c95978cadb3efa789
2021-12-14 02:15:47 +03:00

87 lines
1.8 KiB
Python

# This is practice for various types of list traversals that turn up.
xs = range(10)
n = len(xs)
print('---')
# pythonic left-to-right traversal
result = ''
for x in xs:
result += str(x)
print(result)
print('---')
# left-to-right traversal
result = ''
for i in range(n):
result += str(xs[i])
print(result)
print('---')
# right-to-left traversal
result = ''
for i in range(n):
result += str(xs[n - 1 - i])
print(result)
print('---')
# 2x left-to-right traversal
result = ''
for i in range(2 * n):
result += str(xs[i % n])
print(result)
print('---')
# 2x right-to-left traversal
result = ''
for i in range(2 * n):
result += str(xs[(n - 1 - i) % n])
print(result)
################################################################################
# Table traversals
################################################################################
table = [[row * 10 + i for i in range(10)] for row in range(3)]
row_ct = len(table)
col_ct = len(table[0])
print('---')
# 3x10 table traversal
result = ''
for row in table:
r = ''
for col in row:
r += '{:3d}'.format(col)
result += r + '\n'
print(result[0:-1])
print('---')
# 3x10 table traversal
result = ''
for row in range(row_ct):
r = ''
for col in range(col_ct):
r += '{:3d}'.format(table[row][col])
result += r + '\n'
print(result[0:-1])
print('---')
# 3x10 table traversal (reverse)
result = ''
for row in range(row_ct):
r = ''
for col in range(col_ct):
r += '{:3d}'.format(table[row_ct - 1 - row][col_ct - 1 - col])
result += r + '\n'
print(result)
print('---')
# 3x10 column-row traversal
result = ''
for col in range(col_ct):
r = ''
for row in range(row_ct):
r += '{:3d}'.format(table[row][col])
result += r + '\n'
print(result)