Question

Write a function posnum that prompts the user to enter a positive number and loops to error-check. It returns the square root of the positive number entered by the user. It calls a subfunction in the loop to print an error message. The subfunction has a persistent variable to count the number of times an error has occurred.

Here is an example of calling the function:

>> squarerootvalue = posnum

Enter a positive number: -5

Error #1: Follow instructions!

Does -5.00 look like a positive number to you?

Enter a positive number: -33

Error #2: Follow instructions!

Does -33.00 look like a positive number to you?

Enter a positive number: 4

squarerootvalue = 2

Answer 1

i used c++ langauge.Here is the following code:

============================================

#include <iostream>
#include <cmath> // included to use the sqrt function

using namespace std;

//defining the two functions for finding square root and printing message
void posnum();
void printError(int x);

//persistant variable used to print the error number
static int errorNum=0;

//main function
int main() {
posnum();
}

//definition of functions
void posnum()
{
int num,Squarerootvalue;
cout<<"\nEnter a positive number: ";
cin>>num;
  
if(num>0)
{
Squarerootvalue=sqrt(num);
cout<<"Squarerootvalue =" <<Squarerootvalue<<endl;
}
else
{
printError(num);
posnum();
}

}

void printError(int x)
{
errorNum++;
cout<<"Error #"<<errorNum<<": Follow instructions!"<<endl;
cout<<"Does "<<x<<" look like a positive number to you?";
  
}

please do upvote and comment for doubts.

Looking forward to help you :-)