Input numbers from the keyboard one at a time until the absolute difference between the last two numbers entered is greater than 10.

Use the abs function for this:

int diff = abs(5 - 10);

You should use a while loop to do this. Be careful, it is important to prime the loop properly.

The following is an example run:

Enter a number 3 Enter a number 4 Enter a number 6 Enter a number 11 Enter a number 5 Enter a number 25

The difference between the last two numbers entered is greater than 10.