if statement
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Excute conditionnellement code .
Original:
Conditionally executes code.
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Utilis lorsque le code doit tre excut que si une certaine condition est prsent .
Original:
Used where code needs to be executed only if some condition is present.
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Syntaxe
if ( expression ) statement_true
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if ( expression ) statement_true else statement_false
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Explication
expression doit tre une expression, convertible en
bool .Original:
expression shall be an expression, convertible to
bool.The text has been machine-translated via Google Translate.
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Si elle est value
true, le contrle est pass statement_true, statement_false (si prsent) n'est pas excut .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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Sinon, le contrle est pass statement_false, statement_true n'est pas excut .
Original:
Otherwise, control is passed to statement_false, statement_true is not executed.
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Mots-cls
Exemple
L'exemple suivant illustre l'utilisation de plusieurs cas de la dclaration
if
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';
}
Rsultat :
first is false
i == 3
i != 3 is false