# C++: Programming Problem - Multiplication Table

Write a program to read a number from the user (in a loop of course), and print a multiplication table up to that number.

### Hints

- This is most easily done using nested `for` loops, ie a for loop do go down the rows, which contains a for loop to go accross the columns.

## Example output in increments

As usual, the best approach is to use incremental development. Here are three stages you might want to go thru.

1. The smallest possible output. But it's ugly with unaligned columns.

       1 2 3 4 5
       2 4 6 8 10
       3 6 9 12 15
       4 8 12 16 20
       5 10 15 20 25

2. To make the multiplication table look nice, the I/O manipulator `setw()` can be used to set the minimum width of the converted form of the number.

       #include <iomanip>
       . . .
       cout << setw(4) << n;

   This will right-align the value of `n` in a field of four spaces. The output would look like this.

          1   2   3   4   5
          2   4   6   8  10
          3   6   9  12  15
          4   8  12  16  20
          5  10  15  20  25

3. Add column and row headers as well as separating lines to make it look like the following. Several additional loops are required to print the column header and horizontal separating lines. Don't try to make all of these additions at once. For example, first add the row header and vertical bars. Get that running then print the separating lines. Lastly add the column header. The order of these additions isn't important in this case, but to work on small increments in the program makes development to more easily.

                1     2     3     4     5
            +-----+-----+-----+-----+-----+
          1 |   1 |   2 |   3 |   4 |   5 |
            +-----+-----+-----+-----+-----+
          2 |   2 |   4 |   6 |   8 |  10 |
            +-----+-----+-----+-----+-----+
          3 |   3 |   6 |   9 |  12 |  15 |
            +-----+-----+-----+-----+-----+
          4 |   4 |   8 |  12 |  16 |  20 |
            +-----+-----+-----+-----+-----+
          5 |   5 |  10 |  15 |  20 |  25 |
            +-----+-----+-----+-----+-----+