Given two numbers a and b, build a String that contains every number from a to b, inclusive. But now, in between each pair of numbers, add a space " " character. (The difference between this problem and the previous one is that there should NOT be a space at the end.) Precondition: a < b for all inputs.

HINT: use an if statement to determine when you should add a space. Or, (more creative) use a substring after the loop.