Return Pointer from Functions in C++

As we have seen in last chapter how C++ allows to return an array from a function, similar way C++ allows you to return a pointer from a function. To do so, you would have to declare a function returning a pointer as in the following example −

 int * myFunction() { . . . } 

Second point to remember is that, it is not good idea to return the address of a local variable to outside of the function, so you would have to define the local variable as static variable.

Now, consider the following function, which will generate 10 random numbers and return them using an array name which represents a pointer i.e., address of first array element.

 #include <iostream> #include <ctime> using namespace std; // function to generate and retrun random numbers. int * getRandom( ) { static int r[10]; // set the seed srand( (unsigned)time( NULL ) ); for (int i = 0; i < 10; ++i) { r[i] = rand(); cout << r[i] << endl; } return r; } // main function to call above defined function. int main () { // a pointer to an int. int *p; p = getRandom(); for ( int i = 0; i < 10; i++ ) { cout << "*(p + " << i << ") : "; cout << *(p + i) << endl; } return 0; } 

When the above code is compiled together and executed, it produces result something as follows −

 624723190 1468735695 807113585 976495677 613357504 1377296355 1530315259 1778906708 1820354158 667126415 *(p + 0) : 624723190 *(p + 1) : 1468735695 *(p + 2) : 807113585 *(p + 3) : 976495677 *(p + 4) : 613357504 *(p + 5) : 1377296355 *(p + 6) : 1530315259 *(p + 7) : 1778906708 *(p + 8) : 1820354158 *(p + 9) : 667126415