Answer:
#include <iostream>
using namespace std;
template <typename T> int sgn(T val) {
return (T(0) < val) - (val < T(0));
}
int main()
{
cout << "Enter a number: ";
int number;
cin >> number;
switch (sgn(number)) {
case -1: cout << "The number is negative";
break;
case 0: cout << "The number is zero";
break;
case 1: cout << "The number is positive";
break;
}
}
Explanation:
You need the special sgn() function because a switch() statement can only choose from a list of discrete values (cases).
