Listing 8.11 - Compile Error

[ITHelpDec]

Two changes are needed to get this code to compile:

1. Change line 60 from return last to return (this is a void function, we our not returning an _OutputIterator
2. Make addend a constant reference at line 27

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One further change required to stop the code from crashing at runtime.

1. Complete the join_threadsclass