Nested switch case in C

In this article, we will discuss the nested switch case in C with its example. Before going to the nested switch case, we must know about the switch case.

Switch case is one of the C language's decision control statements. The switch statement is typically used when the user must choose between several options. Switch-case statements replace long if statements that compare a variable with multiple integral values.

The switch statement is a multiway branching statement. It makes it simple to route execution to different areas of code according to the value of the expression. A switch statement is an expression of control that enables a value to shift control of execution.

Syntax:

It has the following syntax:

Consider the following when using Switch Case:

• A switch statement's expression has to be of an integral or characters type or a class type with a single converting function to an integral or character type.
• A switch can contain a limitless amount of case statements. The value being compared against and a colon follow each case.
• When the value of the variable being turned on equals a case, the commands that follow that case will be executed until a break clause is reached.
• When a break statement arrives, the switch is terminated, and control is transferred to the line after the switch statement.
• A break is not required in every situation. If no break appears, control will flow through to consecutive cases until a break is reached, i.e. all case statements will be executed as soon as the compiler determines a comparison to be true.
• A switch statement can include an optional default case, which must conclude. When none of the other situations are true, the default case can be used to complete a task. In the default example, no break is required.

Nested Switch

The switch statement, like any other if, else, etc., permits nesting. It implies that we can write a switch inside a switch and keep executing it continuously. Consider the following example to understand it properly.

Syntax:

It has the following syntax:

Filename: NestedSwitch.c

Output:

The chosen choice is 2

Explanation:

The program takes two variables, x1 and y1, and uses the value of x1 to enter the outer switch expression. If x1 is 1, the value of y1 is further evaluated within a nested switch statement.

In this particular case:

• If x1 is 1 and y1 is 2, the message "The chosen choice is 2" is printed.
• If x1 is 1 and y1 is 3, the message "The chosen choice is 3" is printed.
• If x1 is 4, it prints "The selected option is 3".
• If x1 is 5, it outputs "The selected option is 3".
• If x1 has any other number, it writes, "The Choice is other than 1, 2, 3, 4, or 5".

The outer switch case verifies the value of x1 and, depending on the cases, either executes the nested switch or continues directly to the default case if x1 is not 1, 4, or 5. The program verifies the value of y1 within the nested switch and prints the matching message.

Advantages of Nested Switch Statements:

There are several advantages of Nested Switch Statements. Some main advantages of Nested Switch Statements are as follows:

1. Decision Making: Nested switch statements enable hierarchical decision-making, allowing the computer to assess multiple circumstances in an organized manner.
2. Readability: In certain complex cases, nested switches can improve code readability. Proper indentation and organization can help identify which situations are affected by external factors.
3. Modularity: Nested switching can be used to create code with modular frameworks, particularly when dealing with multi-step procedures with specific scenarios to handle at each phase.

Disadvantages of Nested Switch Statements:

There are several disadvantages of Nested Switch Statements. Some main disadvantages of Nested Switch Statements are as follows:

1. Complexity: As the number of branching increases, the code can become complicated and hard to understand. This complication may result in mistakes during development and maintenance.
2. Difficulties with Debugging: Debugging nested switches can be difficult, especially when attempting to trace control across numerous levels of nested cases.
3. Limited Applicability: Nested switches may sometimes be the most efficient or simple option. Other control frameworks, such as if-else statements or polymorphism (in Object-Based programming), can result in more understandable and maintained code in many circumstances.
4. Maintenance Issues: When improvements are required, making improvements can be error-prone and could result in bugs.
5. Performance: While current compilers have been designed to handle nested switches quickly, deeply nested switches may influence program speed. However, this impact is normally negligible in most circumstances.