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The debugging example below is used for five odd numbers to be sorted. This is the easiest way to figured out how the threads work together with the simple data.
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*How to start debugging
The following sequence may guides you start to debug on the visual Studio.
# put breakpoints where you want to take a look by hitting the key F9 in the line or left-click at the front of a line
# Run the program in Debug mode by hitting the green button (or key F5)
# Go to the menu Debug -> Windows to open the windows you need( see the image on your right)
# Choose the windows that you need (e.g. Memory, Threads, Parallel Stacks, Local or Auto and so on.)
# Hit the function keys to run a program:
## F10 to run codes line by line (Step Over)
## F11 to go into a subroutine (Step Into)
## F9 to put/remove breakpoints in a line
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To open windows you need for debugging on Visual Studio, You must run a program in debug mode first. Otherwise, there is no menu to open the windows.
[[File:debug_windows.png|440px|thumb|left|Menu Debug > Windows on VS 2015]]
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*Sample code results
**Data flow of parallel_qsort
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<tr align="left"><td>[[File:dataflow.png|250px220px|thumb|left|Quick sorting dataflow]]</td><td>Explanation will be here soon.
Fist set of this quick sorting is that main thread worked for first half of all elements which starts *begin 9 to *end 1. The *mid value was 9 so it swapped *mid for *end. Since mid moved to end, the second half of all elements was the end to the end which only end value are to be sorted; the actual process will be skipped so no value is changed.
# Understanding a program is important; using a serial program version, follow codes line by line to understand the program. (Parallel programming usually starts from a serial version.)
# Use the simple data for the first time to keep track of data flow in a memory, and then increase data volume for the program.
# When you missed the step you want to take a look in run-time debug mode, it will be better to start from the beginning in debug mode as data situation have already changed, and threads invocation also has been passed.
# To open windows you need for debugging on Visual Studio, You must run a program in debug mode first. Otherwise, there is no menu to open the windows.
