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feat: add solutions to leetcode problem: No.0281. Zigzag Iterator
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‎solution/0200-0299/0281.Zigzag Iterator/README.md

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@@ -32,27 +32,94 @@ v2 = [3,4,5,6]
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<strong>输出: </strong><code>[1,4,8,2,5,9,3,6,7]</code>.
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</pre>
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## 解法
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<!-- 这里可写通用的实现逻辑 -->
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定义 vectors 列表保存输入的所有一维向量，indexes 表示 vectors 列表每一项当前所遍历到的下标位置，cur 表示当前遍历到的 vector 列表，而 size 表示 vectors 列表元素个数。具体实现参考以下代码实现。
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class ZigzagIterator:
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def __init__(self, v1: List[int], v2: List[int]):
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self.cur = 0
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self.size = 2
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self.indexes = [0] * self.size
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self.vectors = [v1, v2]
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def next(self) -> int:
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vector = self.vectors[self.cur]
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index = self.indexes[self.cur]
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res = vector[index]
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self.indexes[self.cur] = index + 1
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self.cur = (self.cur + 1) % self.size
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return res
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def hasNext(self) -> bool:
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start = self.cur
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while self.indexes[self.cur] == len(self.vectors[self.cur]):
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self.cur = (self.cur + 1) % self.size
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if self.cur == start:
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return False
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return True
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# Your ZigzagIterator object will be instantiated and called as such:
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# i, v = ZigzagIterator(v1, v2), []
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# while i.hasNext(): v.append(i.next())
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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public class ZigzagIterator {
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private int cur;
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private int size;
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private List<Integer> indexes = new ArrayList<>();
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private List<List<Integer>> vectors = new ArrayList<>();
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public ZigzagIterator(List<Integer> v1, List<Integer> v2) {
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cur = 0;
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size = 2;
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indexes.add(0);
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indexes.add(0);
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vectors.add(v1);
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vectors.add(v2);
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}
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public int next() {
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List<Integer> vector = vectors.get(cur);
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int index = indexes.get(cur);
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int res = vector.get(index);
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indexes.set(cur, index + 1);
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cur = (cur + 1) % size;
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return res;
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}
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public boolean hasNext() {
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int start = cur;
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while (indexes.get(cur) == vectors.get(cur).size()) {
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cur = (cur + 1) % size;
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if (start == cur) {
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return false;
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}
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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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* Your ZigzagIterator object will be instantiated and called as such:
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* ZigzagIterator i = new ZigzagIterator(v1, v2);
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* while (i.hasNext()) v[f()] = i.next();
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*/
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```
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### **...**

‎solution/0200-0299/0281.Zigzag Iterator/README_EN.md

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### **Python3**
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```python
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class ZigzagIterator:
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def __init__(self, v1: List[int], v2: List[int]):
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self.cur = 0
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self.size = 2
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self.indexes = [0] * self.size
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self.vectors = [v1, v2]
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def next(self) -> int:
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vector = self.vectors[self.cur]
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index = self.indexes[self.cur]
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res = vector[index]
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self.indexes[self.cur] = index + 1
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self.cur = (self.cur + 1) % self.size
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return res
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def hasNext(self) -> bool:
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start = self.cur
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while self.indexes[self.cur] == len(self.vectors[self.cur]):
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self.cur = (self.cur + 1) % self.size
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if self.cur == start:
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return False
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return True
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# Your ZigzagIterator object will be instantiated and called as such:
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# i, v = ZigzagIterator(v1, v2), []
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# while i.hasNext(): v.append(i.next())
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```
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### **Java**
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```java
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public class ZigzagIterator {
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private int cur;
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private int size;
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private List<Integer> indexes = new ArrayList<>();
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private List<List<Integer>> vectors = new ArrayList<>();
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public ZigzagIterator(List<Integer> v1, List<Integer> v2) {
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cur = 0;
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size = 2;
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indexes.add(0);
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indexes.add(0);
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vectors.add(v1);
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vectors.add(v2);
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}
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public int next() {
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List<Integer> vector = vectors.get(cur);
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int index = indexes.get(cur);
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int res = vector.get(index);
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indexes.set(cur, index + 1);
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cur = (cur + 1) % size;
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return res;
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}
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public boolean hasNext() {
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int start = cur;
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while (indexes.get(cur) == vectors.get(cur).size()) {
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cur = (cur + 1) % size;
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if (start == cur) {
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return false;
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}
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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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* Your ZigzagIterator object will be instantiated and called as such:
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* ZigzagIterator i = new ZigzagIterator(v1, v2);
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* while (i.hasNext()) v[f()] = i.next();
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*/
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```
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### **...**

‎solution/0200-0299/0281.Zigzag Iterator/Solution.java

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public class ZigzagIterator {
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private int cur;
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private int size;
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private List<Integer> indexes = new ArrayList<>();
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private List<List<Integer>> vectors = new ArrayList<>();
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public ZigzagIterator(List<Integer> v1, List<Integer> v2) {
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cur = 0;
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size = 2;
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indexes.add(0);
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indexes.add(0);
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vectors.add(v1);
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vectors.add(v2);
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}
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public int next() {
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List<Integer> vector = vectors.get(cur);
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int index = indexes.get(cur);
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int res = vector.get(index);
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indexes.set(cur, index + 1);
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cur = (cur + 1) % size;
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return res;
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}
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public boolean hasNext() {
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int start = cur;
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while (indexes.get(cur) == vectors.get(cur).size()) {
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cur = (cur + 1) % size;
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if (start == cur) {
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return false;
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}
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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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* Your ZigzagIterator object will be instantiated and called as such:
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* ZigzagIterator i = new ZigzagIterator(v1, v2);
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* while (i.hasNext()) v[f()] = i.next();
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*/

‎solution/0200-0299/0281.Zigzag Iterator/Solution.py

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class ZigzagIterator:
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def __init__(self, v1: List[int], v2: List[int]):
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self.cur = 0
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self.size = 2
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self.indexes = [0] * self.size
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self.vectors = [v1, v2]
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def next(self) -> int:
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vector = self.vectors[self.cur]
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index = self.indexes[self.cur]
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res = vector[index]
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self.indexes[self.cur] = index + 1
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self.cur = (self.cur + 1) % self.size
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return res
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def hasNext(self) -> bool:
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start = self.cur
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while self.indexes[self.cur] == len(self.vectors[self.cur]):
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self.cur = (self.cur + 1) % self.size
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if self.cur == start:
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return False
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return True
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# Your ZigzagIterator object will be instantiated and called as such:
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# i, v = ZigzagIterator(v1, v2), []
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# while i.hasNext(): v.append(i.next())

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