I'm reading some python code and I came across a line of code that says arr = [-1]*n where arr is an array and n is an integer. What does this notation mean? What would arr look like after this?
I feel bad asking this question here, because it feels more like a question for google, but I can't find anything on google by just googling the line of code, and I don't know the name of the notation.
It means, that the resulting array will be that cell repeated n times. In other words it will return an array with n elements when the initial array had one element. Every one of them will be -1 in this case.
In general it will produce an array repeated n-times, for example [1, 2, 3] * 2 == [1, 2, 3, 1, 2, 3].
n. Could you update your answer to make clear that, for example [1, 2] * 2 == [1, 2, 1, 2]?arr = ['z', 'r', 't']
n = 5
arr = [-1] * n
print arr
'''
[-1, -1, -1, -1, -1]
'''
# the values of 'arr' have been changed
arr = [] the answer would still be [-1, -1, -1, -1, -1]
print(arr).