Thread: Passing Array to a Function

take a look

Code:

#include <iostream>
using namespace std;

void input (int test[5])
{
int i;
for(i=0;i<5;i++)
{
cout<<"Enter a number: ";
cin>>test[i];
}
}
int main()
{
int array[5];
input(array);
for(int i=0;i<5;i++)
{
cout<<array[i]; //shows the same values that i have input using the //function
cout<<endl;
}
return 0;
}

I am passing array to function but it is being passed by reference..Could you please explain this concept?
Why is this being passed as reference even though i am not using & operator to pass it as reference. I wrote a bubble sort algorithm using the same concept and i passed the array to function and did not return anything but it sorted the array in my main function which is weird as i did not pass the array by reference. I passed it like in the above program.
Could you guys please explain this?I've been trying to find answer on Google but haven't been able to find it yet.Hopefully you guys can help.

Originally Posted by Salem

Arrays are always passed as a pointer to the first element.

It's as if you did
input( &array[0] );

Which happens regardless of whether you declare your function as
void input (int test[5])
or
void input (int test[])
or
void input (int *test)

Thank you for the explanation.So it is basically passing the address of the first element of the array to the function and then function is able to increment to next element address?..Also, I wrote this little function for my program.Could you please explain what this would return and whether i should remove this line?

Code:

int randomfunc (int random[3][3])
{    
    int rno=5;                                        
    for(row=0;row<3;row++)                                    for(column=1;column<3;column++){                
            random[row][column]=rno%10;
    rno=5+3;
        }

    return random[3][3]; //What would this return?
}
void main()
{
int array[3][3];
array[3][3]=randomfunc(array);
}

It does seem to be producing the correct output (i.e my array now contains random numbers..but could you please explain what would be returned by return random[3][3] and whether i should include it or not?