What does sizeof mean in c language

The sizeof operator calculates the memory size of variables, data types or expressions in C language. Its syntax is sizeof(operand), where operand can be a variable name, data type or an expression in parentheses, and the result is returned. It is an unsigned integer, indicating the number of bytes of the specified operand.

What does sizeof mean in C language?

sizeof operator is used to calculate variables and data in C language The memory size of the type or expression in bytes.

How to use sizeof

The sizeof operator is applied to variable names, data types, or expressions within parentheses. Its syntax is as follows:

<code>sizeof(operand)</code>

where operand can be:

• Variable name
• Data type (such as int, float, char)
• Expression within brackets

sizeof return result

sizeof operator returns a size_t An unsigned integer value of type that represents the memory size of the specified operand.

Example

Consider the following example:

<code class="c">int a = 5;
float b = 3.14;
char c = 'A';</code>

Use the sizeof operator to calculate the memory size of each variable:

<code class="c">printf("sizeof(a) = %ld\n", sizeof(a));  // 4
printf("sizeof(b) = %ld\n", sizeof(b));  // 4
printf("sizeof(c) = %ld\n", sizeof(c));  // 1</code>

Output :

<code>sizeof(a) = 4
sizeof(b) = 4
sizeof(c) = 1</code>

As can be seen from the output:

• int Type variable a occupies 4 bytes of memory.
• float Type variable b also occupies 4 bytes of memory.
• char Type variable c only occupies 1 byte of memory.

The above is the detailed content of What does sizeof mean in c language. For more information, please follow other related articles on the PHP Chinese website!