C++ Switch, Break, Default Statements

The switch statement in C++ is used to control the flow of execution based on the value of an expression. The switch statement is a convenient alternative to multiple if...else statements, especially when you have a large number of cases to test. The basic syntax of the switch statement is as follows:

1switch (expression)
2{
3   case value1:
4      statements;
5      break;
6   case value2:
7      statements;
8      break;
9   ...
10   default:
11      statements;
12}

The expression in the switch statement is evaluated and compared to the values specified in each case statement. When a case value matches the value of the expression, the statements associated with that case are executed.

break statement

The break statement is used to exit the switch statement and continue with the next statement after the switch statement.

default statement

The default case is executed when none of the case values match the value of the expression.

Let's take a look at two examples of the switch statement in C++ and their output:

Example 1: Simple switch Statement with break

1#include <iostream>
2using namespace std;
3
4int main()
5{
6   int number = 2;
7
8   switch (number)
9   {
10      case 1:
11         cout << "The number is 1." << endl;
12         break;
13      case 2:
14         cout << "The number is 2." << endl;
15         break;
16      case 3:
17         cout << "The number is 3." << endl;
18         break;
19   }
20
21   return 0;
22}

In the above example, the switch statement is used to test the value of the number variable. The value of the number variable is 2, which matches the second case statement. The output of the program will be:

1The number is 2.

Example 2: Simple switch Statement with default

1#include <iostream>
2using namespace std;
3
4int main()
5{
6   int number = 4;
7
8   switch (number)
9   {
10      case 1:
11         cout << "The number is 1." << endl;
12         break;
13      case 2:
14         cout << "The number is 2." << endl;
15         break;
16      case 3:
17         cout << "The number is 3." << endl;
18         break;
19      default:
20         cout << "The number is not 1, 2, or 3." << endl;
21   }
22
23   return 0;
24}

In the above example, the switch statement is used to test the value of the number variable. The value of the number variable is 4, which does not match any of the case values. The output of the program will be:

1The number is not 1, 2, or 3.