$(3)$ Question: $8\mathrm{.}10$ LAB $2($Part $1)$: File I$/$O $-$ Sum of integers Implement the function fileSum. fileSum is passed in a name of a file. This function should open the fil...

$8\mathrm{.}10$ LAB $2($Part $1)$: File I$/$O $-$ Sum of integers

Implement the function fileSum. fileSum is passed in a name of a file. This function should open the file, sum all of the integers within this file, close the file, and then return the sum.

If the file does not exist, this function should output an error message and then call the exit function to exit the program with an error value of $1.$

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