The discussion revolves around understanding a Scratch programming code snippet, specifically focusing on the behavior of a variable 'a' and the implications of the "repeat 10" block. Participants explore how the code modifies the value of 'a' through iterations and clarify the difference between "set" and "change by" commands.
Participants generally agree on the mechanics of the "change a by 1" instruction and its implications for the variable 'a', but there is some confusion regarding the initial conditions and the interpretation of the code's behavior. Multiple interpretations of the code's execution remain present.
Some participants express uncertainty about the initial value of 'a' and how it interacts with the loop, highlighting the potential for misunderstanding Scratch's commands.
Individuals new to Scratch programming or those seeking clarification on variable manipulation and control structures in programming.
Ok so if i set a=1. Then a <3 so a*2 = 1*2 = 2. If i repeat this process 10 times , what do i have to do with the a value each time. Add them up ? 2 *10= 20 which is option c) which is wrong. The correct answer is e) 15.Office_Shredder said:
There is no instructionTesla In Person said:
set a to 1, the instruction inside the loop is change a by 1. What is the value of a the first time it reaches this instruction?I thought "change a by 1" meant replace the value of 5 by 1.pbuk said:
You are not the first person to have been caught out by that, it's a confusing "feature" of Scratch.Tesla In Person said:
Yes.Tesla In Person said:
So we add 1 ? It becomes 6 and 6 is not smaller then 3 so we go back and keep adding 1 ? Repeating this 10 times gives a=15 which is correct.pbuk said:
No, as already mentioned. There's a difference between "set" and "change by". "Set" replaces the old value of the variable by some new value. "Change by" adds or subtracts some value to a variable. In the program "change a by 1" adds 1 each time in the loop. If it had said "change a by -2" it would have subtracted 2 each time in the loop.Tesla In Person said:
In the program, a's value is always >= 5, so the if condition is never executed. Essentially what the code does is to increase a (which starts off at 5) by 1 ten times, which results in a's final value being 15.Tesla In Person said: