Collective comms - Quiz
Put what you have learned about Collective communication in OpenFOAM to the test.
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## Basic collective comms
Consider the following code snippet:
```java
// obj.update() returns a bool, whether obj was updated or not.
updated = Foam::returnReduce(obj.update(), andOp());
```
The value of `updated` will:
- [x] Be true if `obj` was updated on all processes.
- [ ] Be true if `obj` was updated on at least one process.
- [ ] Be always false, because `update()` is never called.
## Gathering values from processes
Consider the following code snippet:
```java
label i = random(0, 100); // Generate a random int locally
Pstream::gather(i, maxOp