76 lines
1.2 KiB
Markdown
76 lines
1.2 KiB
Markdown
---
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id: 5900f3711000cf542c50fe84
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title: 问题5：最小的倍数
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challengeType: 5
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videoUrl: ''
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dashedName: problem-5-smallest-multiple
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---
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# --description--
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2520是可以除以1到10中的每个数字而没有任何余数的最小数字。从1到`n`所有数字均可被整除的最小正数是多少？
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# --hints--
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`smallestMult(5)`应该返回60。
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```js
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assert.strictEqual(smallestMult(5), 60);
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```
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`smallestMult(7)`应该返回420。
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```js
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assert.strictEqual(smallestMult(7), 420);
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```
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`smallestMult(10)`应返回2520。
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```js
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assert.strictEqual(smallestMult(10), 2520);
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```
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`smallestMult(13)`应返回360360。
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```js
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assert.strictEqual(smallestMult(13), 360360);
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```
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`smallestMult(20)`应该返回232792560。
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```js
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assert.strictEqual(smallestMult(20), 232792560);
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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 smallestMult(n) {
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return true;
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}
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smallestMult(20);
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```
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# --solutions--
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```js
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function smallestMult(n){
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function gcd(a, b) {
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return b === 0 ? a : gcd(b, a%b); // Euclidean algorithm
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}
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function lcm(a, b) {
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return a * b / gcd(a, b);
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}
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var result = 1;
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for(var i = 2; i <= n; i++) {
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result = lcm(result, i);
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}
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return result;
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}
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```
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