Ternary operator in C++

Introduction

The ternary operator helps you choose between two values quickly in one line. It makes simple decisions easy to write and read.

When you want to assign a value based on a condition without writing a full if-else statement.

When you want to print different messages depending on a condition in a short way.

When you want to return one of two values from a function based on a quick check.

Syntax

C++

condition ? value_if_true : value_if_false;

The condition is checked first.

If the condition is true, the expression returns value_if_true, otherwise it returns value_if_false.

Examples

This sets max to the bigger of a and b.

C++

int a = 10, b = 20;
int max = (a > b) ? a : b;

This checks if num is even and sets isEven accordingly.

C++

bool isEven = (num % 2 == 0) ? true : false;

This prints "Pass" if score is 50 or more, otherwise "Fail".

C++

std::cout << ((score >= 50) ? "Pass" : "Fail") << std::endl;

Sample Program

This program asks for your age and uses the ternary operator to decide if you are an Adult or a Minor, then prints the result.

C++

#include <iostream>
#include <string>

int main() {
    int age;
    std::cout << "Enter your age: ";
    std::cin >> age;

    std::string category = (age >= 18) ? "Adult" : "Minor";

    std::cout << "You are an " << category << "." << std::endl;
    return 0;
}

Important Notes

The ternary operator is best for simple decisions. For complex logic, use if-else statements for clarity.

Both value_if_true and value_if_false should be of compatible types.

Summary

The ternary operator is a short way to choose between two values based on a condition.

It uses the syntax: condition ? value_if_true : value_if_false.

Use it to make your code shorter and easier to read for simple choices.