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    if statement

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    Der Code wird nur ausgeführt, wenn eine bestimmte Bedingung zutrifft.
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    Used where code needs to be executed only if some condition is present.
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    Syntax

    if ( expression ) statement_true
    if ( expression ) statement_true else statement_false

    Erklärung

    expression Ausdruck muss in einen Wahrheitswert bool konvertierbar sein.
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    expression shall be an expression, convertible to bool.
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    Wird der Ausdruck zu true ausgewertet, wird die Steuerung an statement_true übergeben, statement_false (falls vorhanden) wird nicht ausgeführt.
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    If it evaluates to true, control is passed to statement_true, statement_false (if present) is not executed.
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    Andernfalls wird die Steuerung an statement_false übergeben und statement_true wird nicht ausgeführt.
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    Otherwise, control is passed to statement_false, statement_true is not executed.
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    Keywords

    if, else

    Beispiel

    Das folgende Beispiel zeigt mehrere Anwendungsfälle 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