[pull] master from youngyangyang04:master #329

Original file line number	Diff line number	Diff line change
Expand Up		@@ -423,29 +423,61 @@ impl Solution {
		### C:

		```C
	typedef struct HashNodeTag {
	int key; /* num */
	struct HashNodeTag *next;
	}HashNode;

	/* Calcualte the hash key */
	static inline int hash(int key, int size) {
	int index = key % size;
	return (index > 0) ? (index) : (-index);
	}

	/* Calculate the sum of the squares of its digits*/
	static inline int calcSquareSum(int num) {
	unsigned int sum = 0;
	while(num > 0) {
	sum += (num % 10) * (num % 10);
	num = num/10;
	int get_sum(int n) {
	int sum = 0;
	div_t n_div = { .quot = n };
	while (n_div.quot != 0) {
	n_div = div(n_div.quot, 10);
	sum += n_div.rem * n_div.rem;
		}
		return sum;
		}

	// (版本1)使用数组
	bool isHappy(int n) {
	// sum = a1^2 + a2^2 + ... ak^2
	// first round:
	// 1 <= k <= 10
	// 1 <= sum <= 1 + 81 * 9 = 730
	// second round:
	// 1 <= k <= 3
	// 1 <= sum <= 36 + 81 * 2 = 198
	// third round:
	// 1 <= sum <= 81 * 2 = 162
	// fourth round:
	// 1 <= sum <= 81 * 2 = 162

	uint8_t visited[163] = { 0 };
	int sum = get_sum(get_sum(n));
	int next_n = sum;

	while (next_n != 1) {
	sum = get_sum(next_n);

	if (visited[sum]) return false;

	visited[sum] = 1;
	next_n = sum;
	};

	return true;
	}

	// (版本2)使用快慢指针
	bool isHappy(int n) {
	int slow = n;
	int fast = n;

	do {
	slow = get_sum(slow);
	fast = get_sum(get_sum(fast));
	} while (slow != fast);

	return (fast == 1);
	}
	```

	Scala:
	### Scala:
		```scala
		object Solution {
		// 引入mutable
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