74 lines
2.3 KiB
Markdown
74 lines
2.3 KiB
Markdown
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---
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title:Switch Statement
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---
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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.
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Syntax:
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switch(expression) {
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case constant-expression :
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statement(s);
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break; //optional
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case constant-expression :
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statement(s);
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break; //optional
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// you can have any number of case statements.
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default : //Optional
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statement(s);
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}
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The following rules apply to a switch statement −
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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.
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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.
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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.
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When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
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When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
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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.
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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.
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Example:
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```C++
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#include <iostream>
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using namespace std;
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int main () {
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// local variable declaration:
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char grade = 'D';
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switch(grade) {
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case 'A' :
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cout << "Excellent!" << endl;
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break;
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case 'B' :
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case 'C' :
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cout << "Well done" << endl;
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break;
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case 'D' :
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cout << "You passed" << endl;
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break;
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case 'F' :
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cout << "Better try again" << endl;
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break;
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default :
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cout << "Invalid grade" << endl;
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}
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cout << "Your grade is " << grade << endl;
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return 0;
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}```
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Output:
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You passed
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Your grade is D
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###Sources
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https://www.tutorialspoint.com
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