How to use default in C language

default is a keyword in the C language switch statement, used to specify the code block to be executed when there is no matching branch: Syntax: switch (expression) { case value 1: code block 1; break; case Value 2: Code block 2; break; ... default: Default code block; break; }Function: Process all branches that do not have an explicit match. When to use: Make sure the switch statement handles all input values.

Usage of default in C language

#default is a keyword in the switch statement in C language, used Used to specify the code block to be executed when there is no matching branch in the switch.

Syntax:

<code class="c">switch (expression) {
    case value1:
        code block 1;
        break;
    case value2:
        code block 2;
        break;
    ...
    default:
        default code block;
        break;
}</code>

Function:

The default branch is used to process all other branches that do not have an explicit match. It must be placed at the end of the switch statement.

When to use:

Use the default branch to ensure that the switch statement handles all possible input values. If there is no matching branch in switch, the code in the default branch is executed. This is typically used to provide default behavior or handle error conditions.

Example:

<code class="c">switch (ch) {
    case 'A':
        printf("Letter A");
        break;
    case 'B':
        printf("Letter B");
        break;
    default:
        printf("Invalid character");
}</code>

In this example, if the value of ch is 'A' or 'B', the corresponding letter is printed. Otherwise, execute the default branch and print "Invalid character".

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