Conditional (Ternary) Operator in c++ [? :]
The condional operator can often be used instead of the if else statement. Since it is the only operator that requires three operands in c++, it is also called ternary operator.
For example, consider the assignment statement :
x = y > 3 ? 2 : 4;
If y is greater than 3 then 2 will be assigned to variable x or else the value 4 will be assigned to x.
/* A simple c++ program example to demonstrate the use of ternary operator. */
// Program 1
#include <iostream>
#include <iomanip>
using namespace std;
int main ()
{
int first, second;
cout << "Enter two integers." << endl;
cout << "First" << setw (3) << ": ";
cin >> first;
cout << "Second" << setw (2) << ": ";
cin >> second;
string message = first > second ? "first is greater than second" :
             "first is less than or equal to second";
cout << message << endl;
return 0;
}
Compare the above "Program 1" and below "Program 2" with "Program 2" and "Program 3" of Selection Statement (if-else if-else) in c++ respectively, for better understanding.
/* A c++ program example to demonstrate the use ternary operator.*/
// Program 2
#include <iostream>
#include <iomanip>
using namespace std;
int main ()
{
int first, second;
cout << "Enter two integers." << endl;
cout << "First" << setw (3) << ": ";
cin >> first;
cout << "Second" << setw (2) << ": ";
cin >> second;
string message = first > second ? "first is greater than second" :
            first < second ? "first is less than second" :
             "first and second are equal";
cout << message << endl;
return 0;
}