Question

In Python, write a program that asks the user for a positive integer number. If the user enters anything else, the program would ask the user to re-enter a number or enter -1 to quit. If it is a positive number, the program then prints out a multiplication table that goes up to that number. For example, if the user enters 10, the output would look something like this.
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Answer 1

while 1:
    # asking and validating number
    num = input("Enter the number or -1 to quit: ")
    if num == '-1':
        exit()
    elif not num.isdigit():
        print("invalid number ")
    else:
        num = int(num)
        count = 0
        x = 1
        y = 0
        # number of table printed per column
        col_size = 5
        print()
        while num > 0:
            # deciding the column size
            if not count:
                if num >= col_size:
                    y = col_size
                    num -= col_size
                else:
                    y = num
                    num = 0

            if count:
                x = y + 1
                if num >= col_size:
                    y = y + col_size
                    num -= col_size
                else:
                    y = y + num
                    num = 0
            # printing the table
            for i in range(1, 11):
                for j in range(x, y + 1):
                    print("{:<3} x {:<2} = {:<3}".format(j, i, (i * j)), end="  ")
                print()
            print("\n")
            count += 1

# OUTPUT

Enter the number or.-l.to quit: invalid number Enter the number or.-l.to quit: 1x2=2 2x2=4 3x2=6 4x2=8 5x2=10 1x3=3 2x3=6 3x3=9 4x3=12 5x3=15 1x4=4 2x4=8 3x4=12 4x4=165x4=29 1x5=5 2x5=10 3 x5=15 4 x5=295x5=25 1x6=6 2x6=12 3x6=18 4 x6=24 5 x6=30 1x7=7 2x7=14 3 x7=21 4 x7=28 5 x7=35 1x8=8 2x8=16 3 x8=24 4 x8=32 5x8=40 6x2=12 7 x2=148x2=169x2=1810x2=20 6x3=18 7 x3=218x3=24 9 x3=27 10x3=30 6x4=24 7 x4=28 8 x4=32 9x4=36 10x4=40 6 x 7 =42 7 x 7 =49 8 x 7 =56 9 x 7 =63 10 x 7 =70 6x9=54 7 x9=63 8x9=72 9x9=81 10x9=99 Enter the number or.-l.to quit: Process finished with exit code