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57 lines
2.2 KiB
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57 lines
2.2 KiB
HTML
<p>There is a programming language with only <strong>four</strong> operations and <strong>one</strong> variable <code>X</code>:</p>
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<ul>
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<li><code>++X</code> and <code>X++</code> <strong>increments</strong> the value of the variable <code>X</code> by <code>1</code>.</li>
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<li><code>--X</code> and <code>X--</code> <strong>decrements</strong> the value of the variable <code>X</code> by <code>1</code>.</li>
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</ul>
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<p>Initially, the value of <code>X</code> is <code>0</code>.</p>
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<p>Given an array of strings <code>operations</code> containing a list of operations, return <em>the <strong>final </strong>value of </em><code>X</code> <em>after performing all the operations</em>.</p>
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<p> </p>
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<p><strong class="example">Example 1:</strong></p>
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<pre>
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<strong>Input:</strong> operations = ["--X","X++","X++"]
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<strong>Output:</strong> 1
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<strong>Explanation:</strong> The operations are performed as follows:
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Initially, X = 0.
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--X: X is decremented by 1, X = 0 - 1 = -1.
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X++: X is incremented by 1, X = -1 + 1 = 0.
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X++: X is incremented by 1, X = 0 + 1 = 1.
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</pre>
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<p><strong class="example">Example 2:</strong></p>
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<pre>
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<strong>Input:</strong> operations = ["++X","++X","X++"]
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<strong>Output:</strong> 3
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<strong>Explanation: </strong>The operations are performed as follows:
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Initially, X = 0.
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++X: X is incremented by 1, X = 0 + 1 = 1.
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++X: X is incremented by 1, X = 1 + 1 = 2.
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X++: X is incremented by 1, X = 2 + 1 = 3.
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</pre>
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<p><strong class="example">Example 3:</strong></p>
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<pre>
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<strong>Input:</strong> operations = ["X++","++X","--X","X--"]
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<strong>Output:</strong> 0
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<strong>Explanation:</strong> The operations are performed as follows:
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Initially, X = 0.
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X++: X is incremented by 1, X = 0 + 1 = 1.
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++X: X is incremented by 1, X = 1 + 1 = 2.
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--X: X is decremented by 1, X = 2 - 1 = 1.
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X--: X is decremented by 1, X = 1 - 1 = 0.
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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 <= operations.length <= 100</code></li>
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<li><code>operations[i]</code> will be either <code>"++X"</code>, <code>"X++"</code>, <code>"--X"</code>, or <code>"X--"</code>.</li>
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</ul>
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