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38 lines
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38 lines
1.5 KiB
HTML
<p>Given a string <code>num</code> that contains only digits and an integer <code>target</code>, return <em><strong>all possibilities</strong> to insert the binary operators </em><code>'+'</code><em>, </em><code>'-'</code><em>, and/or </em><code>'*'</code><em> between the digits of </em><code>num</code><em> so that the resultant expression evaluates to the </em><code>target</code><em> value</em>.</p>
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<p>Note that operands in the returned expressions <strong>should not</strong> contain leading zeros.</p>
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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> num = "123", target = 6
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<strong>Output:</strong> ["1*2*3","1+2+3"]
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<strong>Explanation:</strong> Both "1*2*3" and "1+2+3" evaluate to 6.
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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> num = "232", target = 8
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<strong>Output:</strong> ["2*3+2","2+3*2"]
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<strong>Explanation:</strong> Both "2*3+2" and "2+3*2" evaluate to 8.
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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> num = "3456237490", target = 9191
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<strong>Output:</strong> []
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<strong>Explanation:</strong> There are no expressions that can be created from "3456237490" to evaluate to 9191.
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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 <= num.length <= 10</code></li>
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<li><code>num</code> consists of only digits.</li>
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<li><code>-2<sup>31</sup> <= target <= 2<sup>31</sup> - 1</code></li>
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</ul>
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