if statement
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Bedingte Ausfhrung.
Original:
Conditionally executes code.
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Der Code wird nur ausgefhrt, wenn eine bestimmte Bedingung zutrifft.
Original:
Used where code needs to be executed only if some condition is present.
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Syntax
if ( expression ) statement_true
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if ( expression ) statement_true else statement_false
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Erklrung
expression Ausdruck muss in einen Wahrheitswert
bool konvertierbar sein.Original:
expression shall be an expression, convertible to
bool.The text has been machine-translated via Google Translate.
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Wird der Ausdruck zu
true ausgewertet, wird die Steuerung an statement_true bergeben, statement_false (falls vorhanden) wird nicht ausgefhrt.Original:
If it evaluates to
true, control is passed to statement_true, statement_false (if present) is not executed.The text has been machine-translated via Google Translate.
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Andernfalls wird die Steuerung an statement_false bergeben und statement_true wird nicht ausgefhrt.
Original:
Otherwise, control is passed to statement_false, statement_true is not executed.
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Keywords
Beispiel
Das folgende Beispiel zeigt mehrere Anwendungsflle des
if Statements
Original:
The following example demonstrates several usage cases of the
if statement
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#include <iostream>
int main()
{
int i = 2;
if (i > 2) {
std::cout << "first is true" << '\n';
} else {
std::cout << "first is false" << '\n';
}
i = 3;
if (i == 3) std::cout << "i == 3" << '\n';
if (i != 3) std::cout << "i != 3" << '\n';
else std::cout << "i != 3 is false" << '\n';
}
Output:
first is false
i == 3
i != 3 is false