First, I will show you the screen shot The screen of vim is divide into two sub windows, the top one can display the code and the bottom one shows the variable you want to watch. Well, this can be changed by you, you can split the window any way you like. You can use C-B to make a break, and press R to run your program, and press S to step, and C-J to add the variable you want to watch. You can do