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Python Exercise: Print out the first n rows of Pascal's triangle

Python Functions: Exercise-13 with Solution

Write a Python function that that prints out the first n rows of Pascal's triangle.

Note : Pascal's triangle is an arithmetic and geometric figure first imagined by Blaise Pascal.

Sample Pascal's triangle :

Pascal's triangle

Each number is the two numbers above it added together

Sample Solution :-

Python Code :

def pascal_triangle(n):
   trow = [1]
   y = [0]
   for x in range(max(n,0)):
      print(trow)
      trow=[l+r for l,r in zip(trow+y, y+trow)]
   return n>=1
pascal_triangle(6) 

Sample Output:

[1]                                                                                                           
[1, 1]                                                                                                        
[1, 2, 1]                                                                                                     
[1, 3, 3, 1]                                                                                                  
[1, 4, 6, 4, 1]                                                                                               
[1, 5, 10, 10, 5, 1]  

Flowchart:

Flowchart: Python exercises: Print out the first n rows of Pascal's tringle.

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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}