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| 1 | +<p>A <strong>0-indexed</strong> array <code>derived</code> with length <code>n</code> is derived by computing the <strong>bitwise XOR</strong> (⊕) of adjacent values in a <strong>binary array</strong> <code>original</code> of length <code>n</code>.</p> |
| 2 | + |
| 3 | +<p>Specifically, for each index <code>i</code> in the range <code>[0, n - 1]</code>:</p> |
| 4 | + |
| 5 | +<ul> |
| 6 | + <li>If <code>i = n - 1</code>, then <code>derived[i] = original[i] ⊕ original[0]</code>.</li> |
| 7 | + <li>Otherwise, <code>derived[i] = original[i] ⊕ original[i + 1]</code>.</li> |
| 8 | +</ul> |
| 9 | + |
| 10 | +<p>Given an array <code>derived</code>, your task is to determine whether there exists a <strong>valid binary array</strong> <code>original</code> that could have formed <code>derived</code>.</p> |
| 11 | + |
| 12 | +<p>Return <em><strong>true</strong> if such an array exists or <strong>false</strong> otherwise.</em></p> |
| 13 | + |
| 14 | +<ul> |
| 15 | + <li>A binary array is an array containing only <strong>0's</strong> and <strong>1's</strong></li> |
| 16 | +</ul> |
| 17 | + |
| 18 | +<p> </p> |
| 19 | +<p><strong class="example">Example 1:</strong></p> |
| 20 | + |
| 21 | +<pre> |
| 22 | +<strong>Input:</strong> derived = [1,1,0] |
| 23 | +<strong>Output:</strong> true |
| 24 | +<strong>Explanation:</strong> A valid original array that gives derived is [0,1,0]. |
| 25 | +derived[0] = original[0] ⊕ original[1] = 0 ⊕ 1 = 1 |
| 26 | +derived[1] = original[1] ⊕ original[2] = 1 ⊕ 0 = 1 |
| 27 | +derived[2] = original[2] ⊕ original[0] = 0 ⊕ 0 = 0 |
| 28 | +</pre> |
| 29 | + |
| 30 | +<p><strong class="example">Example 2:</strong></p> |
| 31 | + |
| 32 | +<pre> |
| 33 | +<strong>Input:</strong> derived = [1,1] |
| 34 | +<strong>Output:</strong> true |
| 35 | +<strong>Explanation:</strong> A valid original array that gives derived is [0,1]. |
| 36 | +derived[0] = original[0] ⊕ original[1] = 1 |
| 37 | +derived[1] = original[1] ⊕ original[0] = 1 |
| 38 | +</pre> |
| 39 | + |
| 40 | +<p><strong class="example">Example 3:</strong></p> |
| 41 | + |
| 42 | +<pre> |
| 43 | +<strong>Input:</strong> derived = [1,0] |
| 44 | +<strong>Output:</strong> false |
| 45 | +<strong>Explanation:</strong> There is no valid original array that gives derived. |
| 46 | +</pre> |
| 47 | + |
| 48 | +<p> </p> |
| 49 | +<p><strong>Constraints:</strong></p> |
| 50 | + |
| 51 | +<ul> |
| 52 | + <li><code>n == derived.length</code></li> |
| 53 | + <li><code>1 <= n <= 10<sup>5</sup></code></li> |
| 54 | + <li>The values in <code>derived</code> are either <strong>0's</strong> or <strong>1's</strong></li> |
| 55 | +</ul> |
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