Not the exact one perhaps, but there are a lot of arrangement problems in the preceding pages. It is always better if try to work out a problem yourself with a few hints than if you are handed down the solution.
As for your question, try doing it with two nested loops, one for the upper triangle including the middle line and another to print the bottom half of the diamond. For the upper triangle the number of spaces at the beginning of a line is equal to n - i, where i is the line number of thecurrent line and n the line number of the middle line.