if statement - cppreference.com
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Executa condicionalmente código.
Original:
Conditionally executes code.
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Usado onde o código precisa ser executado somente se alguma condição está presente.
Original:
Used where code needs to be executed only if some condition is present.
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Sintaxe
if ( expression ) statement_true
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if ( expression ) statement_true else statement_false
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Explicação
expression deve ser uma expressão, conversível a bool.
Original:
expression shall be an expression, convertible to bool.
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Se é avaliada como true, o controle é passado para statement_true, statement_false (se houver) não é executado.
Original:
If it evaluates to true, control is passed to statement_true, statement_false (if present) is not executed.
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Caso contrário, o controle é passado para statement_false, statement_true não é executado.
Original:
Otherwise, control is passed to statement_false, statement_true is not executed.
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Palavras-chave
Exemplo
O exemplo seguinte demonstra o uso de vários casos a instrução 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'; }
Saída:
first is false i == 3 i != 3 is false