C ++ conditional operator?:

C ++ operator

Exp1 ? Exp2 : Exp3;

Wherein, Exp1, Exp2 and Exp3 expression. Please note the use of the colon and location. ?: Expression depends on the value of the calculation result Exp1. If Exp1 is true, then the calculated value Exp2 calculation results and compared the entire Exp2:? Expression. If Exp1 is false, the value Exp3 calculated and compared with the results Exp3 whole:? Expression.

? Is called the ternary operator because it requires three operands, as shown below can be used instead of if-else statement:

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

For example, consider the following code:

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

The above code can be written in the following statement:

var = (y < 10) ? 30 : 40;

Here, if y is less than 10, then var is assigned 30, if y is not less than 10, then var is assigned 40. Consider the following examples:

#include <iostream>
using namespace std;
 
int main ()
{
   // 局部变量声明
   int x, y = 10;

   x = (y < 10) ? 30 : 40;

   cout << "value of x: " << x << endl;
 
   return 0;
}

When the above code is compiled and executed, it produces the following results:

value of x: 40

C ++ operator