No difference between the lists but why different outputs

help
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image1015×504 7 KB

2

This is a well-known Python two-dimensional array trap.

7*[1] actually generates a pointer to [1,1,1,1,1,1,1,1], and h is actually made up of five identical pointers, so modifying one value modifies all five at the same time.

A correct way to generate large two-dimensional arrays in Python would look like this

h=[]
for i in range(0,5):
   h.append([1]*7)
4

OK. Thank You, got it!