Merge branch 'youngyangyang04:master' into remote

problems/0844.比较含退格的字符串.md

@@ -205,6 +205,42 @@ class Solution:
         return self.get_string(s) == self.get_string(t)
         pass
 ```
+双指针
+```python
+class Solution:
+    def backspaceCompare(self, s: str, t: str) -> bool:
+        s_index, t_index = len(s) - 1, len(t) - 1
+        s_backspace, t_backspace = 0, 0 # 记录s,t的#数量
+        while s_index >= 0 or t_index >= 0: # 使用or，以防长度不一致
+            while s_index >= 0: # 从后向前，消除s的#
+                if s[s_index] == '#':
+                    s_index -= 1
+                    s_backspace += 1
+                else:
+                    if s_backspace > 0:
+                        s_index -= 1
+                        s_backspace -= 1
+                    else:
+                        break
+            while t_index >= 0: # 从后向前，消除t的#
+                if t[t_index] == '#':
+                    t_index -= 1
+                    t_backspace += 1
+                else:
+                    if t_backspace > 0:
+                        t_index -= 1
+                        t_backspace -= 1
+                    else:
+                        break
+            if s_index >= 0 and t_index >= 0: # 后半部分#消除完了，接下来比较当前位的值
+                if s[s_index] != t[t_index]:
+                    return False
+            elif s_index >= 0 or t_index >= 0: # 一个字符串找到了待比较的字符，另一个没有，返回False
+                return False
+            s_index -= 1
+            t_index -= 1
+        return True
+```
 
 ### Go 
 
@@ -226,6 +262,51 @@ func backspaceCompare(s string, t string) bool {
 	return getString(s) == getString(t)
 }
 
+```
+双指针
+```go
+func backspaceCompare(s string, t string) bool {
+    s_index, t_index := len(s) - 1, len(t) - 1
+    s_backspace, t_backspace := 0, 0 // 记录s,t的#数量
+    for s_index >= 0 || t_index >= 0 { // 使用or，以防长度不一致
+        for s_index >= 0 { // 从后向前，消除s的#
+            if s[s_index] == '#' {
+                s_index--
+                s_backspace++
+            } else {
+                if s_backspace > 0 {
+                    s_index--
+                    s_backspace--
+                } else {
+                    break
+                }
+            }            
+        }
+        for t_index >= 0 { // 从后向前，消除t的#
+            if t[t_index] == '#' {
+                t_index--
+                t_backspace++
+            } else {
+                if t_backspace > 0 {
+                    t_index--
+                    t_backspace--
+                } else {
+                    break
+                }
+            }            
+        }
+        if s_index >= 0 && t_index >= 0 { // 后半部分#消除完了，接下来比较当前位的值
+            if s[s_index] != t[t_index] {
+                return false
+            } 
+        } else if s_index >= 0 || t_index >= 0 { // 一个字符串找到了待比较的字符，另一个没有，返回false
+            return false
+        }            
+        s_index--
+        t_index--
+    }      
+    return true
+}
 ```
 
 ### JavaScript 

problems/剑指Offer58-II.左旋转字符串.md

@@ -209,6 +209,61 @@ var reverseLeftWords = function(s, n) {
 };
 ```
 
+版本二（在原字符串上操作）：
+
+```js
+/**
+ * @param {string} s
+ * @param {number} n
+ * @return {string}
+ */
+var reverseLeftWords = function (s, n) {
+    /** Utils */
+    function reverseWords(strArr, start, end) {
+        let temp;
+        while (start < end) {
+            temp = strArr[start];
+            strArr[start] = strArr[end];
+            strArr[end] = temp;
+            start++;
+            end--;
+        }
+    }
+    /** Main code */
+    let strArr = s.split('');
+    let length = strArr.length;
+    reverseWords(strArr, 0, length - 1);
+    reverseWords(strArr, 0, length - n - 1);
+    reverseWords(strArr, length - n, length - 1);
+    return strArr.join('');
+};
+```
+
+TypeScript：
+
+```typescript
+function reverseLeftWords(s: string, n: number): string {
+    /** Utils */
+    function reverseWords(strArr: string[], start: number, end: number): void {
+        let temp: string;
+        while (start < end) {
+            temp = strArr[start];
+            strArr[start] = strArr[end];
+            strArr[end] = temp;
+            start++;
+            end--;
+        }
+    }
+    /** Main code */
+    let strArr: string[] = s.split('');
+    let length: number = strArr.length;
+    reverseWords(strArr, 0, length - 1);
+    reverseWords(strArr, 0, length - n - 1);
+    reverseWords(strArr, length - n, length - 1);
+    return strArr.join('');
+};
+```
+
 Swift:
 
 ```swift