diff --git a/problems/0121.买卖股票的最佳时机.md b/problems/0121.买卖股票的最佳时机.md
index f0bc3b97..a2498bb6 100644
--- a/problems/0121.买卖股票的最佳时机.md
+++ b/problems/0121.买卖股票的最佳时机.md
@@ -426,6 +426,46 @@ var maxProfit = function(prices) {
};
```
+TypeScript:
+
+> 贪心法
+
+```typescript
+function maxProfit(prices: number[]): number {
+ if (prices.length === 0) return 0;
+ let buy: number = prices[0];
+ let profitMax: number = 0;
+ for (let i = 1, length = prices.length; i < length; i++) {
+ profitMax = Math.max(profitMax, prices[i] - buy);
+ buy = Math.min(prices[i], buy);
+ }
+ return profitMax;
+};
+```
+
+> 动态规划
+
+```typescript
+function maxProfit(prices: number[]): number {
+ /**
+ dp[i][0]: 第i天持有股票的最大现金
+ dp[i][1]: 第i天不持有股票的最大现金
+ */
+ const length = prices.length;
+ if (length === 0) return 0;
+ const dp: number[][] = [];
+ dp[0] = [-prices[0], 0];
+ for (let i = 1; i < length; i++) {
+ dp[i] = [];
+ dp[i][0] = Math.max(dp[i - 1][0], -prices[i]);
+ dp[i][1] = Math.max(dp[i - 1][0] + prices[i], dp[i - 1][1]);
+ }
+ return dp[length - 1][1];
+};
+```
+
+
+
-----------------------
diff --git a/problems/0122.买卖股票的最佳时机II(动态规划).md b/problems/0122.买卖股票的最佳时机II(动态规划).md
index 5a165a14..12b21fde 100644
--- a/problems/0122.买卖股票的最佳时机II(动态规划).md
+++ b/problems/0122.买卖股票的最佳时机II(动态规划).md
@@ -295,6 +295,42 @@ const maxProfit = (prices) => {
}
```
+TypeScript:
+
+> 动态规划
+
+```typescript
+function maxProfit(prices: number[]): number {
+ /**
+ dp[i][0]: 第i天持有股票
+ dp[i][1]: 第i天不持有股票
+ */
+ const length: number = prices.length;
+ if (length === 0) return 0;
+ const dp: number[][] = new Array(length).fill(0).map(_ => []);
+ dp[0] = [-prices[0], 0];
+ for (let i = 1; i < length; i++) {
+ dp[i][0] = Math.max(dp[i - 1][0], dp[i - 1][1] - prices[i]);
+ dp[i][1] = Math.max(dp[i - 1][1], dp[i - 1][0] + prices[i]);
+ }
+ return dp[length - 1][1];
+};
+```
+
+> 贪心法
+
+```typescript
+function maxProfit(prices: number[]): number {
+ let resProfit: number = 0;
+ for (let i = 1, length = prices.length; i < length; i++) {
+ if (prices[i] > prices[i - 1]) {
+ resProfit += prices[i] - prices[i - 1];
+ }
+ }
+ return resProfit;
+};
+```
+
-----------------------
diff --git a/problems/0123.买卖股票的最佳时机III.md b/problems/0123.买卖股票的最佳时机III.md
index 56ade343..67c99497 100644
--- a/problems/0123.买卖股票的最佳时机III.md
+++ b/problems/0123.买卖股票的最佳时机III.md
@@ -352,6 +352,36 @@ const maxProfit = prices => {
};
```
+TypeScript:
+
+> 版本一
+
+```typescript
+function maxProfit(prices: number[]): number {
+ /**
+ dp[i][0]: 无操作;
+ dp[i][1]: 第一次买入;
+ dp[i][2]: 第一次卖出;
+ dp[i][3]: 第二次买入;
+ dp[i][4]: 第二次卖出;
+ */
+ const length: number = prices.length;
+ if (length === 0) return 0;
+ const dp: number[][] = new Array(length).fill(0)
+ .map(_ => new Array(5).fill(0));
+ dp[0][1] = -prices[0];
+ dp[0][3] = -prices[0];
+ for (let i = 1; i < length; i++) {
+ dp[i][0] = dp[i - 1][0];
+ dp[i][1] = Math.max(dp[i - 1][1], -prices[i]);
+ dp[i][2] = Math.max(dp[i - 1][2], dp[i - 1][1] + prices[i]);
+ dp[i][3] = Math.max(dp[i - 1][3], dp[i - 1][2] - prices[i]);
+ dp[i][4] = Math.max(dp[i - 1][4], dp[i - 1][3] + prices[i]);
+ }
+ return Math.max(dp[length - 1][2], dp[length - 1][4]);
+};
+```
+
Go:
> 版本一:
diff --git a/problems/0142.环形链表II.md b/problems/0142.环形链表II.md
index e8ca950d..f8e62d45 100644
--- a/problems/0142.环形链表II.md
+++ b/problems/0142.环形链表II.md
@@ -370,7 +370,31 @@ ListNode *detectCycle(ListNode *head) {
}
```
-
+Scala:
+```scala
+object Solution {
+ def detectCycle(head: ListNode): ListNode = {
+ var fast = head // 快指针
+ var slow = head // 慢指针
+ while (fast != null && fast.next != null) {
+ fast = fast.next.next // 快指针一次走两步
+ slow = slow.next // 慢指针一次走一步
+ // 如果相遇,fast快指针回到头
+ if (fast == slow) {
+ fast = head
+ // 两个指针一步一步的走,第一次相遇的节点必是入环节点
+ while (fast != slow) {
+ fast = fast.next
+ slow = slow.next
+ }
+ return fast
+ }
+ }
+ // 如果fast指向空值,必然无环返回null
+ null
+ }
+}
+```
-----------------------
diff --git a/problems/0242.有效的字母异位词.md b/problems/0242.有效的字母异位词.md
index 878b2466..8fd9c604 100644
--- a/problems/0242.有效的字母异位词.md
+++ b/problems/0242.有效的字母异位词.md
@@ -308,6 +308,32 @@ impl Solution {
}
```
+
+Scala:
+```scala
+object Solution {
+ def isAnagram(s: String, t: String): Boolean = {
+ // 如果两个字符串的长度不等,直接返回false
+ if (s.length != t.length) return false
+ val record = new Array[Int](26) // 记录每个单词出现了多少次
+ // 遍历字符串,对于s字符串单词对应的记录+=1,t字符串对应的记录-=1
+ for (i <- 0 until s.length) {
+ record(s(i) - 97) += 1
+ record(t(i) - 97) -= 1
+ }
+ // 如果不等于则直接返回false
+ for (i <- 0 until 26) {
+ if (record(i) != 0) {
+ return false
+ }
+ }
+ // 如果前面不返回false,说明匹配成功,返回true,return可以省略
+ true
+ }
+}
+```
+
+
C#:
```csharp
public bool IsAnagram(string s, string t) {
@@ -326,6 +352,7 @@ C#:
return true;
}
```
+
## 相关题目
* 383.赎金信
diff --git a/problems/背包理论基础01背包-1.md b/problems/背包理论基础01背包-1.md
index d2ab191a..a40a92ab 100644
--- a/problems/背包理论基础01背包-1.md
+++ b/problems/背包理论基础01背包-1.md
@@ -380,53 +380,31 @@ func main() {
### javascript
```js
-/**
- *
- * @param {Number []} weight
- * @param {Number []} value
- * @param {Number} size
- * @returns
- */
+function testWeightBagProblem (weight, value, size) {
+ // 定义 dp 数组
+ const len = weight.length,
+ dp = Array(len).fill().map(() => Array(size + 1).fill(0));
-function testWeightBagProblem(weight, value, size) {
-const len = weight.length,
-dp = Array.from({length: len}).map(
-() => Array(size + 1)) //JavaScript 数组是引用类型
-for(let i = 0; i < len; i++) { //初始化最左一列,即背包容量为0时的情况
-dp[i][0] = 0;
-}
-for(let j = 1; j < size+1; j++) { //初始化第0行, 只有一件物品的情况
-if(weight[0] <= j) {
-dp[0][j] = value[0];
-} else {
-dp[0][j] = 0;
-}
-}
-
-for(let i = 1; i < len; i++) { //dp[i][j]由其左上方元素推导得出
-for(let j = 1; j < size+1; j++) {
-if(j < weight[i]) dp[i][j] = dp[i - 1][j];
-else dp[i][j] = Math.max(dp[i-1][j], dp[i-1][j - weight[i]] + value[i]);
-}
-}
-
-return dp[len-1][size] //满足条件的最大值
-}
-
-function testWeightBagProblem2 (wight, value, size) {
- const len = wight.length,
- dp = Array(size + 1).fill(0);
- for(let i = 1; i <= len; i++) {
- for(let j = size; j >= wight[i - 1]; j--) {
- dp[j] = Math.max(dp[j], value[i - 1] + dp[j - wight[i - 1]]);
+ // 初始化
+ for(let j = weight[0]; j <= size; j++) {
+ dp[0][j] = value[0];
}
- }
- return dp[size];
-}
+ // weight 数组的长度len 就是物品个数
+ for(let i = 1; i < len; i++) { // 遍历物品
+ for(let j = 0; j <= size; j++) { // 遍历背包容量
+ if(j < weight[i]) dp[i][j] = dp[i - 1][j];
+ else dp[i][j] = Math.max(dp[i - 1][j], dp[i - 1][j - weight[i]] + value[i]);
+ }
+ }
+
+ console.table(dp)
+
+ return dp[len - 1][size];
+}
function test () {
- console.log(testWeightBagProblem([1, 3, 4, 5], [15, 20, 30, 55], 6));
+ console.log(testWeightBagProblem([1, 3, 4, 5], [15, 20, 30, 55], 6));
}
test();