ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
93 lines
2.3 KiB
Markdown
93 lines
2.3 KiB
Markdown
---
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id: 5a23c84252665b21eecc7e80
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title: 格雷码
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challengeType: 5
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videoUrl: ''
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dashedName: gray-code
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---
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# --description--
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[格雷码](<https://en.wikipedia.org/wiki/Gray code>)是二进制编码的一种形式，其中连续数字之间的转换仅相差一位。这是一种有用的编码，用于减少硬件数据危险，其值快速变化和/或连接到较慢的硬件作为输入。从左到右或从上到下依次为[卡诺图](<https://en.wikipedia.org/wiki/Karnaugh map>)生成输入也很有用。创建一个函数来编码数字并解码格雷码中的数字。该函数应该有2个参数。第一个是布尔值。该函数应编码为true，解码为false。第二个参数是要编码/解码的数字。显示所有5位二进制数的正常二进制表示，格雷码表示和解码格雷码值（0-31包括0，不需要前导0）。有许多可能的格雷码。以下编码所谓的“二进制反射格雷码”。
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编码（MSB为0位，b为二进制，g为格雷码）： <code><br>if b[i-1] = 1<br><span style='padding-left:1em'>g[i] = not b[i]</span><br>else<br><span style='padding-left:1em'>g[i] = b[i]</span><br></code>要么：
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`g = b xor (b logically right shifted 1 time)`
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解码（MSB为0位，b为二进制，g为格雷码）：
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<code>b[0] = g[0]<br>for other bits:<br>b[i] = g[i] xor b[i-1]<br></code>
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# --hints--
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`gray`应该是一个功能。
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```js
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assert(typeof gray == 'function');
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```
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`gray(true,177)`应该返回一个数字。
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```js
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assert(typeof gray(true, 177) == 'number');
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```
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`gray(true,177)`应该返回`233` 。
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```js
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assert.equal(gray(true, 177), 233);
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```
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`gray(true,425)`应该返回`381` 。
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```js
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assert.equal(gray(true, 425), 381);
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```
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`gray(true,870)`应该返回`725` 。
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```js
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assert.equal(gray(true, 870), 725);
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```
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`gray(false,233)`应该返回`177` 。
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```js
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assert.equal(gray(false, 233), 177);
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```
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`gray(false,381)`应该返回`425` 。
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```js
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assert.equal(gray(false, 381), 425);
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```
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`gray(false,725)`应该返回`870` 。
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```js
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assert.equal(gray(false, 725), 870);
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```
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# --seed--
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## --seed-contents--
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```js
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function gray(enc, number) {
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}
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```
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# --solutions--
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```js
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function gray(enc, number){
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if(enc){
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return number ^ (number >> 1);
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}else{
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let n = number;
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while (number >>= 1) {
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n ^= number;
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}
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return n;
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}
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}
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```
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