2018-10-10 18:03:03 -04:00
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---
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id: 594810f028c0303b75339acf
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2020-12-16 00:37:30 -07:00
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title: 阿克曼功能
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2018-10-10 18:03:03 -04:00
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challengeType: 5
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videoUrl: ''
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2021-01-13 03:31:00 +01:00
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dashedName: ackermann-function
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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<p> Ackermann函数是递归函数的典型示例,尤其值得注意的是它不是原始递归函数。它的值增长非常快,其调用树的大小也是如此。 </p><p> Ackermann函数通常定义如下: </p> $$ A(m,n)= \\ begin {cases} n + 1&\\ mbox {if} m = 0 \\\\ A(m-1,1)&\\ mbox {if} m> 0 \\ mbox {和} n = 0 \\\\ A(m-1,A(m,n-1))&\\ mbox {if} m> 0 \\ mbox {和} n> 0. \\ end {cases} $$ <p>它的论点永远不会消极,它总是终止。编写一个返回$ A(m,n)$的值的函数。任意精度是首选(因为函数增长如此之快),但不是必需的。 </p>
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`ack`是一个功能。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(typeof ack === 'function');
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```
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`ack(0, 0)`应该返回1。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(ack(0, 0) === 1);
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`ack(1, 1)`应该返回3。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(ack(1, 1) === 3);
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`ack(2, 5)`应该返回13。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(ack(2, 5) === 13);
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`ack(3, 3)`应该返回61。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(ack(3, 3) === 61);
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2018-10-10 18:03:03 -04:00
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```
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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function ack(m, n) {
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}
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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```js
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function ack(m, n) {
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return m === 0 ? n + 1 : ack(m - 1, n === 0 ? 1 : ack(m, n - 1));
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}
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```
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