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43 lines
1.5 KiB
HTML
43 lines
1.5 KiB
HTML
<p>Return the result of evaluating a given boolean <code>expression</code>, represented as a string.</p>
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<p>An expression can either be:</p>
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<ul>
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<li><code>"t"</code>, evaluating to <code>True</code>;</li>
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<li><code>"f"</code>, evaluating to <code>False</code>;</li>
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<li><code>"!(expr)"</code>, evaluating to the logical NOT of the inner expression <code>expr</code>;</li>
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<li><code>"&(expr1,expr2,...)"</code>, evaluating to the logical AND of 2 or more inner expressions <code>expr1, expr2, ...</code>;</li>
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<li><code>"|(expr1,expr2,...)"</code>, evaluating to the logical OR of 2 or more inner expressions <code>expr1, expr2, ...</code></li>
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</ul>
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<p> </p>
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<p><strong>Example 1:</strong></p>
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<pre>
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<strong>Input:</strong> expression = "!(f)"
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<strong>Output:</strong> true
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</pre>
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<p><strong>Example 2:</strong></p>
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<pre>
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<strong>Input:</strong> expression = "|(f,t)"
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<strong>Output:</strong> true
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</pre>
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<p><strong>Example 3:</strong></p>
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<pre>
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<strong>Input:</strong> expression = "&(t,f)"
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<strong>Output:</strong> false
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</pre>
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<p> </p>
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<p><strong>Constraints:</strong></p>
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<ul>
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<li><code>1 <= expression.length <= 2 * 10<sup>4</sup></code></li>
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<li><code>expression[i]</code> consists of characters in <code>{'(', ')', '&', '|', '!', 't', 'f', ','}</code>.</li>
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<li><code>expression</code> is a valid expression representing a boolean, as given in the description.</li>
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</ul>
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