No, because if variable=variable-1 if you try and solve using math, you will get 0=-1; if done with programming, it will set the variable to something new.
The variable can affect all sprites scripts or just one sprite script.
I dont know what the intent is but if you set x to y and y to x nothing has changed. All the values maintain their original status.
Value #2 and value #1 are changing positions.
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