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C++ Conditional statements

if-else

• if
• else
• else if

Ternary operator

Or shorthand if-else.

Condense an if-else expression in a single statement.

[(type)] [variable] = [condition] ? [value_if_true] : [value_if_false];

int number = 10;

std::string is_10 = (number == 10) ? "yes" : "no";

Omitting brackets

Curly brackets{} can be omitted if there is only one statement inside an if, else if or else block.

if (number == 7)
    std::cout << "nice";

// same as:
if (number == 7) {
    std::cout << "nice too";
    }

⚠ It is better not to ommit the brackets.

switch statement

int grade = 9;

switch (grade) {
    case 9:
        std::cout << "Freshman";
        break;
    case 10:
        std::cout << "Sophomore";
        break;
    default:
        std::cout << "Invalid";
        break;
}

If the break keyword was ommited, and the value of grade was 9, the case 10 would also be executed. This type of bug is called a fallthrough.