# Hands-on: Collective operations

In this exercise we test different routines for collective communication.
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In this exercise we test different routines for collective communication.
Source code for this exercise is located in mpi/collectives/
First, write a program where rank 0 sends an array containing numbers from 0
to 7 to all the other ranks using collective communication.
Next, we continue with four MPI tasks with following initial data vectors:

in the buffer are initialized to -1. Implement a program that sends and
receives values from the data vectors to receive buffers using a single
collective communication routine for each case, so that the receive buffers
will have the following values. You can start from the skeleton file
skeleton.py.

### Case 3

Tip: create two communicators
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