Turning a list comprehension into a for loop-CodePudding

I ma trying to tunr the list comprehension codes trow=[left right for left,right in zip(trow y, y trow)] into a for loop instead of a list comprehension. I have attempted to do this conversion but it does not work. How will I be able to do this?

For loop Code:

def PascalTriangle(n):
   trow = [1]
   y = [0]
   for x in range(n):
      print(trow)
      for left,right in zip(trow y, y trow):
        trow.append(left right)
   return n>=1

PascalTriangle(6)

List comprehension Code:

def PascalTriangle(n):
   trow = [1]
   y = [0]
   for x in range(n):
      print(trow)
      trow=[left right for left,right in zip(trow y, y trow)]
   return n>=1

PascalTriangle(6)

Output:

[1]
[1, 1, 1]
[1, 1, 1, 1, 2, 2, 1]
[1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 3, 4, 3, 1]
[1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 3, 4, 3, 1, 1, 2, 2, 2, 3, 4, 3, 2, 3, 4, 4, 5, 7, 7, 4, 1]
[1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 3, 4, 3, 1, 1, 2, 2, 2, 3, 4, 3, 2, 3, 4, 4, 5, 7, 7, 4, 1, 1, 2, 2, 2, 3, 4, 3, 2, 3, 4, 4, 5, 7, 7, 4, 2, 3, 4, 4, 5, 7, 7, 5, 5, 7, 8, 9, 12, 14, 11, 5, 1]

Expected Output:

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

CodePudding user response：

You could use a temporary list to collect all values:

def PascalTriangle(n):
    trow = [1]
    y = [0]

    for x in range(n):
        print(trow)
        line = []
        for left, right in zip(trow   y, y   trow):
            line.append(left   right)
        trow = line
    return n >= 1


PascalTriangle(6)

Out:

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