The function could now either have three parameters, one the new value still pased by value, the others passed by reference (with an & in front), or it could have two parameters and use its return value to return one of the two it generates, while it uses a reference parameter to return the other. If you use three parameters, you can make the function into a void function.
Whatever you do, you must still have the new value being passed by value, not by reference.
This is fairly straightforward. You will need to use parentheses to allow you to access members of the struct. Thus:
allows you to access element field1 in the struct st1 passed by reference. You will see more on this in the next note and in the note on accessing via pointers to structs.
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