freeCodeCamp/guide/english/cplusplus/switch-statements/index.md

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---
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title: Switch Statement
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---
A switch statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each case.
Syntax:
switch(expression) {
case constant-expression :
statement(s);
break; //optional
case constant-expression :
statement(s);
break; //optional
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// you can have any number of case statements.
default : //Optional
statement(s);
}
The following rules apply to a switch statement
The expression used in a switch statement must have an integral or enumerated type, or be of a class type in which the class has a single conversion function to an integral or enumerated type.
You can have any number of case statements within a switch. Each case is followed by the value to be compared to and a colon.
The constant-expression for a case must be the same data type as the variable in the switch, and it must be a constant or a literal.
When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
Not every case needs to contain a break. If no break appears, the flow of control will fall through to subsequent cases until a break is reached.
A switch statement can have an optional default case, which must appear at the end of the switch. The default case can be used for performing a task when none of the cases is true. No break is needed in the default case.
Example:
```C++
#include <iostream>
using namespace std;
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int main () {
// local variable declaration:
char grade = 'D';
switch(grade) {
case 'A' :
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cout << "Excellent!" << endl;
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break;
case 'B' :
case 'C' :
cout << "Well done" << endl;
break;
case 'D' :
cout << "You passed" << endl;
break;
case 'F' :
cout << "Better try again" << endl;
break;
default :
cout << "Invalid grade" << endl;
}
cout << "Your grade is " << grade << endl;
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return 0;
}```
Output:
You passed
Your grade is D
###Sources
https://www.tutorialspoint.com