33 lines
929 B
Markdown
33 lines
929 B
Markdown
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---
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title: Largest prime factor
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localeTitle: 最大的素因子
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---
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## 问题3：最大的素因子
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### 方法：
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* 为了找到一个数字的最大素数因子，我们从最小的素数因子2开始并用它来除数。
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* 如果余数为0表示该数字可以被该素数整除，我们将数字除以相同的素数，直到该数字不再被该素数整除。
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* 之后，我们将素因子增加1并重复此过程，直到数字变为1。
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### 解：
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```js
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function largestPrimeFactor(number) {
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let prime = 2, max = 1;
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while (prime <= number){
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if (number % prime == 0) {
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max = prime;
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number = number/prime;
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}
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else prime++; //Only increment the prime number if the number isn't divisible by it
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}
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return max;
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}
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```
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* [运行代码](https://repl.it/@ezioda004/Problem-3-Largest-prime-factor)
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### 资源：
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* [维基百科](https://en.wikipedia.org/wiki/Prime_number)
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