C++ Conditional operator ? :

C++ Operator

Exp1　? Exp2　: Exp3;

where, Exp1, Exp2 and Exp3 is an expression. Please note the use and position of the colon. The value of the ? : expression depends on Exp1 The result of the calculation.1 is true, then calculate Exp2 The value, and Exp2 The result of the calculation is the value of the entire ? : expression. If Exp1 is false, then calculate Exp3 The value, and Exp3 The result of the calculation is the value of the entire ? : expression.

? is called the ternary operator because it requires three operands, and can be used to replace the following if-else statement:

if(condition){
　　　var = X;
}
　　　var = Y;
}

For example, please see the following code segment:

if(y <　10{　
　　　var =　30;
}
　　　var =　40;
}

The above code can be written as follows:

var = (y <　10) ?　30 :　40;

Here, if y is less than 10, then var is assigned the value 30, if y is not less than 10, then var is assigned the value 40. See the following example:

#include <iostream>
using namespace std;
　
int main ()
{
　　　//　Local Variable Declaration
　　　int x, y =　10;
　
　　　x = (y <　10) ?　30 :　40;
　
　　　cout << "The value of x: " << x << endl;
　
　　　return 0;
}

When the above code is compiled and executed, it will produce the following result:

The value of x:　40

C++ Operator