Printing a Multiplication Table With Nested Loops

Printing a multiplication table with nested loops?

Low-Level: Your code shows two '|' after each number because that's what you're telling it to do (one of them is passed to print() right after num, and one of them is added by the use of end='|', which tells print() to add a '|' at the end of the printed string).

Using end='' avoids the second '|', but you still end up with a pipe character at the end of each row from the print() call.

To get '|' between items, but not at the end of the row, you need to handle the last item in each row specially (or, better use " | ".join(row) to add the separators automatically).

High-Level: You're likely not solving this problem the way it was intended to be solved.

Your answer hard-codes the multiplication table, but you could be generating it as part of the loop, like:

# Store the size of the table here 
# So it's easy to change later
maximum = 3
# Make a row for each y value in [1, maximum]
for y in range(1, maximum + 1):
    # Print all x * y except the last one, with a separator afterwards and no newline
    for x in range(1, maximum):
        print(x * y, end=' | ')
    # Print the last product, without a separator, and with a newline
    print(y * maximum)

This solves the specific problem given, but we can now change the value of "maximum" to also generate a square multiplication table of any size, and we don't have to worry about errors in our multiplication table.

How can a multiplication table be displayed using only nested for loops and System.out.println in Java?

This is something that you will learn in any beginners book:

for (int i=1;i<=10;i++){
  for (int j=1;j<=10;j++)
     System.out.print("\t"+i*j);
  System.out.println(); 
}

Multiplication Table using Nested Loops

How to print multiplication table using nested for loops

One of the simplest methods would be to start counting from 0 instead of 1:

for row in range(0, 10):
    for col in range(0, 10):
        num = row * col
        if num < 10:
            empty = "  "
        else:
            if num < 100: 
                empty  = " " 
        if col == 0:
            if row == 0:
                print("    ", end = '')
            else:
                print("  ", row, end='')
        elif row == 0:
            print("  ", col, end='')
        else:
            print(empty, num, end = '')
    print()

this will print

    1   2   3   4   5   6   7   8   9
1   1   2   3   4   5   6   7   8   9
2   2   4   6   8  10  12  14  16  18
3   3   6   9  12  15  18  21  24  27
4   4   8  12  16  20  24  28  32  36
5   5  10  15  20  25  30  35  40  45
6   6  12  18  24  30  36  42  48  54
7   7  14  21  28  35  42  49  56  63
8   8  16  24  32  40  48  56  64  72
9   9  18  27  36  45  54  63  72  81

That being said, here is a one-liner version that results in the same output:

print("\n".join(("{:>4}"*10).format(*(i*j if i*j else i+j if i+j else "" for j in range(10))) for i in range(10)))

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