mirror of
https://github.com/youngyangyang04/leetcode-master.git
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Merge branch 'master' of https://github.com/youngyangyang04/leetcode-master
This commit is contained in:
@ -388,6 +388,44 @@ class Solution:
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res += res1
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return res
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```
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动态规划
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```python3
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class Solution:
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def trap(self, height: List[int]) -> int:
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leftheight, rightheight = [0]*len(height), [0]*len(height)
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leftheight[0]=height[0]
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for i in range(1,len(height)):
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leftheight[i]=max(leftheight[i-1],height[i])
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rightheight[-1]=height[-1]
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for i in range(len(height)-2,-1,-1):
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rightheight[i]=max(rightheight[i+1],height[i])
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result = 0
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for i in range(0,len(height)):
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summ = min(leftheight[i],rightheight[i])-height[i]
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result += summ
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return result
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```
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单调栈
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```python3
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class Solution:
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def trap(self, height: List[int]) -> int:
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st =[0]
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result = 0
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for i in range(1,len(height)):
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while st!=[] and height[i]>height[st[-1]]:
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midh = height[st[-1]]
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st.pop()
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if st!=[]:
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hright = height[i]
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hleft = height[st[-1]]
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h = min(hright,hleft)-midh
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w = i-st[-1]-1
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result+=h*w
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st.append(i)
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return result
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```
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Go:
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@ -191,4 +191,57 @@ public:
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这里我依然建议大家按部就班把版本一写出来,把情况一二三分析清楚,然后在精简代码到版本二。 直接看版本二容易忽略细节!
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## 其他语言版本
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Java:
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Python:
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动态规划
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```python3
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class Solution:
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def largestRectangleArea(self, heights: List[int]) -> int:
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result = 0
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minleftindex, minrightindex = [0]*len(heights), [0]*len(heights)
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minleftindex[0]=-1
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for i in range(1,len(heights)):
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t = i-1
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while t>=0 and heights[t]>=heights[i]: t=minleftindex[t]
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minleftindex[i]=t
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minrightindex[-1]=len(heights)
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for i in range(len(heights)-2,-1,-1):
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t=i+1
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while t<len(heights) and heights[t]>=heights[i]: t=minrightindex[t]
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minrightindex[i]=t
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for i in range(0,len(heights)):
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left = minleftindex[i]
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right = minrightindex[i]
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summ = (right-left-1)*heights[i]
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result = max(result,summ)
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return result
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```
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单调栈 版本二
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```python3
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class Solution:
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def largestRectangleArea(self, heights: List[int]) -> int:
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heights.insert(0,0) # 数组头部加入元素0
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heights.append(0) # 数组尾部加入元素0
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st = [0]
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result = 0
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for i in range(1,len(heights)):
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while st!=[] and heights[i]<heights[st[-1]]:
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midh = heights[st[-1]]
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st.pop()
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if st!=[]:
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minrightindex = i
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minleftindex = st[-1]
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summ = (minrightindex-minleftindex-1)*midh
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result = max(summ,result)
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st.append(i)
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return result
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```
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<div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码.jpg width=450> </img></div>
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@ -159,7 +159,7 @@ public:
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return false;
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}
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que.push(leftNode->left); // 添加p节点的左子树节点
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que.push(rightNode->left); // 添加q节点的左子树节点点
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que.push(rightNode->left); // 添加q节点的左子树节点
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que.push(leftNode->right); // 添加p节点的右子树节点
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que.push(rightNode->right); // 添加q节点的右子树节点
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}
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@ -1205,6 +1205,35 @@ public:
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};
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```
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java代码:
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```java
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class Solution {
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public Node connect(Node root) {
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Queue<Node> tmpQueue = new LinkedList<Node>();
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if (root != null) tmpQueue.add(root);
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while (tmpQueue.size() != 0){
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int size = tmpQueue.size();
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Node cur = tmpQueue.poll();
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if (cur.left != null) tmpQueue.add(cur.left);
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if (cur.right != null) tmpQueue.add(cur.right);
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for (int index = 1; index < size; index++){
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Node next = tmpQueue.poll();
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if (next.left != null) tmpQueue.add(next.left);
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if (next.right != null) tmpQueue.add(next.right);
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cur.next = next;
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cur = next;
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}
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}
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return root;
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}
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}
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```
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python代码:
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@ -209,6 +209,22 @@ class Solution(object):
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return True
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```
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Python写法四:
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```python3
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class Solution:
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def canConstruct(self, ransomNote: str, magazine: str) -> bool:
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c1 = collections.Counter(ransomNote)
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c2 = collections.Counter(magazine)
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x = c1 - c2
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#x只保留值大于0的符号,当c1里面的符号个数小于c2时,不会被保留
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#所以x只保留下了,magazine不能表达的
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if(len(x)==0):
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return True
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else:
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return False
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```
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Go:
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```go
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@ -9,6 +9,7 @@
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# 925.长按键入
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题目链接:https://leetcode-cn.com/problems/long-pressed-name/
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你的朋友正在使用键盘输入他的名字 name。偶尔,在键入字符 c 时,按键可能会被长按,而字符可能被输入 1 次或多次。
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你将会检查键盘输入的字符 typed。如果它对应的可能是你的朋友的名字(其中一些字符可能被长按),那么就返回 True。
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@ -98,7 +99,36 @@ public:
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# 其他语言版本
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Java:
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```java
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class Solution {
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public boolean isLongPressedName(String name, String typed) {
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int i = 0, j = 0;
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int m = name.length(), n = typed.length();
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while (i< m && j < n) {
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if (name.charAt(i) == typed.charAt(j)) { // 相同则同时向后匹配
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i++; j++;
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}
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else {
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if (j == 0) return false; // 如果是第一位就不相同直接返回false
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// 判断边界为n-1,若为n会越界,例如name:"kikcxmvzi" typed:"kiikcxxmmvvzzz"
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while (j < n-1 && typed.charAt(j) == typed.charAt(j-1)) j++;
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if (name.charAt(i) == typed.charAt(j)) { // j跨越重复项之后再次和name[i]匹配
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i++; j++; // 相同则同时向后匹配
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}
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else return false;
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}
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}
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// 说明name没有匹配完
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if (i < m) return false;
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// 说明type没有匹配完
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while (j < n) {
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if (typed.charAt(j) == typed.charAt(j-1)) j++;
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else return false;
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}
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return true;
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}
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}
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```
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Python:
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```python
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class Solution:
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@ -169,6 +169,7 @@ class Solution {
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}
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}
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```
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Python
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```python
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class Solution:
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def commonChars(self, words: List[str]) -> List[str]:
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@ -30,7 +30,7 @@
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2. 空间复杂度是准确算出程序运行时所占用的内存么?
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不要以为空间复杂度就已经精准的掌握了程序的内存使用大小,很有多因素会影响程序真正内存使用大小,例如编译器的内存对齐,编程语言容器的底层实现等等这些都会影响到程序内存的开销。
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不要以为空间复杂度就已经精准的掌握了程序的内存使用大小,很多因素会影响程序真正内存使用大小,例如编译器的内存对齐,编程语言容器的底层实现等等这些都会影响到程序内存的开销。
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所以空间复杂度是预先大体评估程序内存使用的大小。
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@ -141,6 +141,18 @@ class Solution:
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# 空间复杂度:O(n),python的string为不可变,需要开辟同样大小的list空间来修改
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```
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```python 3
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#方法三:考虑不能用切片的情况下,利用模+下标实现
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class Solution:
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def reverseLeftWords(self, s: str, n: int) -> str:
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new_s = ''
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for i in range(len(s)):
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j = (i+n)%len(s)
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new_s = new_s + s[j]
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return new_s
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```
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Go:
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||||
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```go
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||||
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Reference in New Issue
Block a user