i have done this code which can do add, sub, mul, div and square. But this much function is not sufficient for a calculator. I want to add one exponential function and one square root function. plz help me frens

Code:`#include <iostream>`

int main()

{

double num;

double num2;

char choice;

for (;;){

do {

cout<<"\n";

cout<<"Welcome to apex calculator.\n";

cout<<"Please choose an option by entering the number, press q to quit\n";

cout<<"1 - Addition\n";

cout<<"2 - Subtraction\n";

cout<<"3 - Division\n";

cout<<"4 - Multiplication\n";

cout<<"5 - Help\n";

cout<<"6 - About This Program\n";

cout<<"7 - find square\n";

cin>>choice;

} while ( choice < '1' || choice > '7' && choice != 'q');

if (choice == 'q') break;

switch (choice) {

case '1':

cout<<"Please enter a number\n";

cin>>num;

cout<<"Another number to be added\n";

cin>>num2;

cout<<num + num2;

cout<<"\n";

break;

case '2':

cout<<"Please enter a number\n";

cin>>num;

cout<<"Another number to be subtracted\n";

cin>>num2;

cout<<num - num2;

cout<<"\n";

break;

case '3':

cout<<"Please enter a number\n";

cin>>num;

cout<<"Another one to be divided\n";

cin>>num2;

cout<<num / num2;

cout<<"\n";

break;

case '4':

cout<<"Please enter a number\n";

cin>>num;

cout<<"Another one to be multiplied\n";

cin>>num2;

cout<<num * num2;

cout<<"\n";

break;

case '5':

cout<<"This is a simple calculator made by bishal, manoj, pramesh and ram\n";

cout<<"To select an option, type the number next to the option and press enter\n";

cout<<"E.G. for division, you would type 3 and press enter.\n";

cout<<"\n";

break;

case '6':

cout<<" apex calculator, made by bishal, manoj, pramesh and ram \n";

cout<<"\n";

break;

case '7':

cout<<"please enter a number\n";

cin>>num;

cout<<"the square is \t "<<num*num;

cout<<"\n";

break;

default:

cout<<"That is not an option";

}

}

return 0;

}