.DEMO


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F3
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+This demo describes the test mode of the Roo environment. Press any key.
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+Press a key every time you have read a message in this line.
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+One of the basic skills we want to teach...
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+...is the skill of tracing somebody else's program.
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+If a student can trace programs then he understands the logic of programs,
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+...and basic concepts of programming.
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+The purpose of the test mode is to check whether a student has such a skill.
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+Now the demo will show you one test.
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^S
BS BS BS BS BS BS BS BS BS BS
:test
ET
Y
+Chris will be an examiner.
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+You see: he asks a question "Is the condition met" which means in this case...
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+..."Can Roo move forward?". Apparently no, so press "N".
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N
+Now we have to show the command that Roo must execute next.
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+This should be the first command of the second branch of this branching...
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DN @ DN @ DN
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+
ET
+Now Chris has to go to the subroutine T. Demo will put the red arrow there.
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DN @ DN @ DN @ DN
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+
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+Next question. The answer is "Yes", of course. But let us make a mistake...
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+...and press "N". Watch the dialog between Chris and Roo.
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N
+Chris indicates and records all our mistakes (and the time spent for answers).
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+The condition is met so Chris has to go to the first command of the cycle.
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DN
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+
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+The cycle is finished. Chris has to return to the while-heading.
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UP @ UP
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+
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+The condition of the cycling is not met. Press "N".
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N
+The cycling is finished so Chris has to escape it. But suppose we made...
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+...another mistake. Demo will put the arrow at the next line.
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DN
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+Chris indicates the mistake and shows the correct answer.
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ET
+The subroutine is finished and Chris has to return back to the head program:
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UP @ UP @ UP @ UP @ UP @ UP @ UP
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+
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+The branching is finished and Chris has to leave it.
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DN
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+
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+The test is over. The following statistics will be saved on the disk.
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