infoarena

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eu votez 10 in baza 2 sau 10 pastrez suspans :)

deci... intrebarea e care e numarul maxim de coliziuni care pot aparea? (coliziune= moment in care doua sau mai multe fire incearca sa incrementeze variabila in aproape acelasi timp; daca asta se intampla variabila va fi incrementata numai de un fir, si anume de primul, sau nu va fi incrementata deloc? );

The fact that you chose python for this code is very confusing to me.

Think of it as a pseudocode example, instead of Python if that makes it less confusing :).

Python threading sucks but the code is somewhat shorter than a Java equivalent.

@t3st your example has a small bug.

2:
Thread 1 reads value 0
Thread 2 does 9 iterations, thread 3-5 all their 10 iterations (the ordering doesn't matter)
Thread 1 writes value 1
Thread 2 reads value 1
Thread 1 reads and writes etc until it completes all its iterations
Thread 2 writes value 2

Basically what t3st said, he was just missing "thread 1 completes the rest of the iterations" before thread 2 does the final write.

As Radu and others have said the answer is 2.

Radu, I've tried with more threads and more increments and you start seeing interesting numbers even if Python uses GIL.