C++: Write a recursive function named sumSquares that returns the sum of the squares of the numbers from 0 to num, in which num is a nonnegative int variable. Do not use global variables; use the appropriate parameters. Also, write a program to test your function.

So I wrote the code but I need help with the error handling on when the user enters zero and a program to test my function.

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#include

#include

using namespace std;

// set the variable

int sumSquares(int num);

int main()

{

// variables for the while loops

string answer;

char yes, no;

// a while loop for possiblilty of more than one entry

while (true)

{

//prompt the user for a number

cout << "Please input a number to sum the squares from 1 to that number: " << endl;

// get that number

int num;

cin >> num;

cout << " Sum is " << sumSquares(num) << endl;

// ask the user if they want to type another number

cout << " Do you want enter another number (yes or no)" << endl;

cin >> answer;

// if no is entered the program exits or yes and the program goes back to the begining

if (answer == "no" || answer == "No")

break;

}// end while loop

}

int sumSquares(int num)

{

// for when the user enters 0

if (num == 0)

{

return 0;

}

// as long as the number is positive

else

{

return num * num + sumSquares(num - 1);

}

}