How do arrays work in functions?

[avatar97]

I'm trying to sort a lot of data in a text file so I'm trying to create a function to make things easier. In my function I'm trying to store values in a string array like this: example[j]="word". In my function I increment j because the function is being called in a loop in main so the next spot in example[] will have to be used. However when I try to print the full array it only prints the last word entered to example[]. When I use the same code in main instead of calling the function the full array prints. What's going on?
PS sorry I didn't post my code its kind of all over the place right now since I'm testing but if you need to see it to help I can post it

[jonnin]

the name of an array may as well be a pointer, so passing an array is passing by reference.

I am going to go WAY, WAY out on a limb here and tell you to put the keyword static in front of J and tell me if that helped.

that is, static int j;
...
j++;
etc

[avatar97]

that didn't work; I assume you meant to put static in front of j in the function inputs because that's where j is. There is no for loop except for when I'm trying to print the array. I'm using a while loop to read the file data and in that loop I'm calling the function. Like I said when I do it without the function it works but that's pretty cumbersome. Anyways, I'll do some research the array pointer u mentioned, thanks.

[Cubbi]

If you're using C++ rather than C, the array's type should be std::vector<std::string>, Especially given that you're reading data from a file, how would you know how big the array shoudl be ahead of time?

In my function I'm trying to store values in a string array ... I'm using a while loop to read the file data and in that loop I'm calling the function.

that would look something like this:

#include <iostream>
#include <string>
#include <vector>
#include <fstream>

void add_to(std::vector<std::string>& v, const std::string s) {
    v.push_back(s);
}
void print(std::vector<std::string>& v) {
    for(const std::string& s: v) std::cout << s << '\n';
}
int main()
{
  std::vector<std::string> v;
  std::string s;
  std::ifstream f("test.txt");
  while(f >> s) add_to(v, s);
  print(v);
}

live demo: http://coliru.stacked-crooked.com/a/b677a3318aab183b

(of course if you already know all about vectors and strings and are getting into advanced topics such as arrays it's another story)

[jonnin]

we probably need to see the function body.