Summary  
The ternary operator provides a concise alternative to if-else statements by evaluating a condition and returning one of two expressions, improving code readability and conciseness while advising against deep nesting.

General domain of usage  
Conditional decision-making in code

The **ternary operator** is a powerful tool that often used to make quick decisions in your code and can greatly improve code **readability** when used appropriately.

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The condition is evaluated. If the condition is `true`, the expression before the `:` is executed, otherwise, the expression after the `:` is executed.

**The ternary operator** is essentially just an alternative to the if-else statement, providing the code **readability and convenience**.

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As you can see it using **ternary operator** can save code space and improve *readability* and *efficiency*. However, it is important to save a balance and maintain code **maintainability** and **understandability**. 

**Ternary operators** can also be nested to handle more complex conditions. But **don't** fall into a pitfall full of **ternary operators**.

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It's really hard to understand what is going on. So it is better to limit yourself to a single **ternary operator**, with a maximum of <u>one level of nesting</u> at any given time.

#define CATCH_CONFIG_MAIN
#include <catch2/catch.hpp>
#include <string>

std::string evaluatePerformance(int score1, int score2, int score3);

TEST_CASE("Average >= 85 should return 'Excellent'", "[evaluatePerformance]") {
    int s1 = 90, s2 = 85, s3 = 95;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Excellent");
}

TEST_CASE("Average >= 70 and < 85 should return 'Good'", "[evaluatePerformance]") {
    int s1 = 70, s2 = 80, s3 = 75;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Good");
}

TEST_CASE("Average >= 50 and < 70 should return 'Average'", "[evaluatePerformance]") {
    int s1 = 50, s2 = 60, s3 = 55;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Average");
}

TEST_CASE("Average < 50 should return 'Fail'", "[evaluatePerformance]") {
    int s1 = 40, s2 = 45, s3 = 50;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Fail");
}

TEST_CASE("Edge case: average exactly 85 => 'Excellent'", "[evaluatePerformance]") {
    int s1 = 85, s2 = 85, s3 = 85;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Excellent");
}

TEST_CASE("Edge case: average exactly 70 => 'Good'", "[evaluatePerformance]") {
    int s1 = 70, s2 = 70, s3 = 70;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Good");
}

TEST_CASE("Edge case: average exactly 50 => 'Average'", "[evaluatePerformance]") {
    int s1 = 50, s2 = 50, s3 = 50;
    REQUIRE(evaluatePerformance(s1, s2, s3) == "Average");
}

test.cpp

Welcome to a beginner-friendly course that will help you learn the core concepts of conditional statements . Whether you're new to programming or looking to improve your understanding of conditional statements and how they influence the flow of your programs, this course is designed to meet your needs.

This is your gateway to understanding the fundamental building blocks of decision making. Gain the essential knowledge to make your programs more intelligent and responsive.

Challenge: Ternary Operator

解答