Answers for "make a 2d list"

how to initialize a 2d list in python

# Using above second method to create a
# 2D array
rows, cols = (5, 5)
arr = [[0 for i in range(cols)] for j in range(rows)]
print(arr)

how to create 2d list in python

o=[]
for i in range(0,rows):
    x=[]
    for j in range(0,cols):
        x.append(0)
    o.append(x)
#if you use [[0]*cols]*rows all rows will become the same list
#so editing in one row will edit all rows

python declare 2d list

length, breadth = x, y
matrix = [[-1 for j in range(breadth)] for i in range(length)]
# every element is -1