![]() ![]() ![]() ( ): parentheses are used to group words or phrases when combining synonyms, such as (gun or pistol or firearm or rifle) or Boolean phrases. Parentheses also may be used to show the order in which relationships should be considered (like in algebra!).For example, the search statement ”copyright piracy” will retrieve records that contain the exact phrase “copyright piracy.” The search would not, however, retrieve documents that use the separate terms in a different order. This is possible through Boolean operators such as AND, OR, NOT, and NEAR, as well as the symbols + (add) and - (subtract). ![]() “ “: the placement of search terms in quotation marks is used to retrieve documents containing the exact phrase enclosed in the quotation marks. A Boolean search, in the context of a search engine, is a type of search where you can use special words or symbols to limit, widen, or define your search.For example, the search statement piracy NOT copyright will retrieve documents that contain the word piracy, but not the word copyright. NOT: the operator NOT, or BUT NOT, or the percent sign (%), is used to narrow a search and to retrieve records that do not contain the term following it.For example, the search statement copyright OR piracy will retrieve documents that contain the word copyright or the word piracy, but not necessarily in the same document. OR: the operator OR, or a space between words in most databases, is used to broaden a search and to retrieve records containing any of the words it separates.For example, the search statement copyright AND piracy will retrieve documents that contain the words copyright and piracy. AND: the operator AND, or an ampersand (&), is used to retrieve documents containing all of the words that it separates. Boolean Search is a search process that allows you to broaden, limit, and define your search options by adding Boolean Search Operators or Modifiers within.Let’s look at some variable declarations more closely: bool var1 // declaration of a boolean variable>īool var2 = true // declaration and initialization of a boolean variableīool var3 = 1 // alternative declaration and initialization of a boolean variable>īool vectorIncludes(vector &v, const T& key) Mind that, var1 is not initialized and since the C++ standard does not specify, you should not expect it to have true or false value when printed to the cout stream. The said feature of C++ booleans is demonstrated in the following code snippet, which also prints the values of the declared boolean variables to the console. On the other hand, assigning a zero value or null pointer to the boolean variable will set its value to false. If you searched online for your old friend Jack Russell just by typing his name, you’d get. Boolean Operators are simple words (AND, OR, NOT or AND NOT) used as conjunctions to combine or exclude keywords in a search, resulting in more focused and. We should note that assigning true or 1 to the boolean variable will have the same effect, but it’s preferable to use the true keyword when initializing variables. Boolean NOT, NOT-OR The easiest way to explain the NOT operator is to compare it to an Internet search. The latter ones are represented in C++ with keywords true/false, and their type is bool. C++ boolean variables can be initialized by assigning integer values to them or by special keywords called boolean literals. Boolean searches work by combining words and phrases with one or more words, known as operators, to limit, widen and define what youre searching for. Like any other variable, we can declare C++ boolean type using a bool keyword followed by the name of the variable itself. Implicit conversion rules for C++ booleans.Include C++ booleans in bit-fields to access single bits.Use C++ booleans to implement comparison operators.Use C++ booleans as return values for functions. ![]()
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