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Python: Print a heap as a tree-like data structure

Python heap queue algorithm: Exercise-19 with Solution

Write a Python program to print a heap as a tree-like data structure.

Sample Solution:

Python Code:

import math
from io import StringIO
#source https://bit.ly/38HXSoU
def show_tree(tree, total_width=60, fill=' '):
    """Pretty-print a tree.
    total_width depends on your input size"""
    output = StringIO()
    last_row = -1
    for i, n in enumerate(tree):
        if i:
            row = int(math.floor(math.log(i+1, 2)))
        else:
            row = 0
        if row != last_row:
            output.write('\n')
        columns = 2**row
        col_width = int(math.floor((total_width * 1.0) / columns))
        output.write(str(n).center(col_width, fill))
        last_row = row
    print (output.getvalue())
    print ('-' * total_width)
    return

#test
import heapq
heap = []
heapq.heappush(heap, 1)
heapq.heappush(heap, 2)
heapq.heappush(heap, 3)
heapq.heappush(heap, 4)
heapq.heappush(heap, 7)
heapq.heappush(heap, 9)
heapq.heappush(heap, 10)
heapq.heappush(heap, 8)
heapq.heappush(heap, 16)
heapq.heappush(heap, 14)
show_tree(heap)

Sample Output:

                             1                              
              2                             3               
       4              7              9              10      
   8      16     14  
------------------------------------------------------------

Flowchart:

Python heap queue algorithm: Print a heap as a tree-like data structure.

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Python: Tips of the Day

Creates a dictionary with the same keys as the provided dictionary and values generated by running the provided function for each value:

Example:

def tips_map_values(obj, fn):
  ret = {}
  for key in obj.keys():
    ret[key] = fn(obj[key])
  return ret
users = {
  'Owen': { 'user': 'Owen', 'age': 29 },
  'Eddie': { 'user': 'Eddie', 'age': 15 }
}

print(tips_map_values(users, lambda u : u['age'])) # {'Owen': 29, 'Eddie': 15}

Output:

{'Owen': 29, 'Eddie': 15}