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c#multiplicationtabular

Multiplication table structure


Question about structure of this multiplication table..

How do I make spaces so the output would be like this:

      1 X 9 + 2 = 11
     12 X 9 + 3 = 111
    123 X 9 + 4 = 1111
   1234 X 9 + 5 = 11111
  12345 X 9 + 6 = 111111
 123456 X 9 + 7 = 1111111
1234567 X 9 + 8 = 11111111

Code:

#region MTABLE

int number1 = 1;

for (int i = 2; i <= 8; i++)

{
    int number2 = number1 * 9 + i;
    Console.WriteLine("{0} x {1} + {2} = {3}  ", number1, 9, i, number2);
    number1 = number1 * 10 + i;

    for (int j = 1; j <= i; j++)
    Console.Write(" ");
}

Console.ReadKey();

#endregion

My code currently outputs:

1 x 9 + 2 = 11
  12 x 9 + 3 = 111
   123 x 9 + 4 = 1111
    1234 x 9 + 5 = 11111
     12345 x 9 + 6 = 111111
      123456 x 9 + 7 = 1111111
       1234567 x 9 + 8 = 11111111

Solution

  • Move the inner loop to the beginning of the outer loop and count backwards from 8-i:

    for (int i = 2; i <= 8; i++)
    {
        for (int j = 8-i; j >0; j--)
            Console.Write(" ");
    
        int number2 = number1 * 9 + i;
        Console.WriteLine("{0} x {1} + {2} = {3}  ", number1, 9, i, number2);
        number1 = number1 * 10 + i;
    }