In C, the function return type specifies the value type returned to the caller after the function is called. Steps include: Selecting a data type that matches the expected return value (such as int, float, char, bool). Place a declaration of the selected type before the function name (such as int get_number()).
Guidelines for specifying function return types in C
In C, function return types are integral to function signatures A part used to specify the value type returned to the caller after the function is called. To specify a function return type, follow these steps:
Step 1: Select a data type
Select a C data type that corresponds to the expected return value. For example:
- Integer type: int, long, short
- Floating point type: float, double, long double
- Character type: char, wchar_t
- Boolean type: bool
- Custom type (class or structure)
Step 2: Place the type declaration before the function name
Place the declaration of the selected type before the function name. For example:
// 返回整数 int get_number(); // 返回浮点数 float calculate_average(); // 返回一个字符串 std::string create_message();
Practical example:
Consider a function that calculates the sum of two numbers:
// 返回两个数字的和 int add_numbers(int num1, int num2) { return num1 + num2; }
In this case, the expected function returns An integer, so we use int type as the return type.
Note:
- If the function does not return a value, you need to use void as the return type.
- If the function returns a reference, you need to use a reference type (&), such as std::string&.
- Function can return any data type, including pointers, arrays and even other functions.
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