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feat: add solutions to lc problem: No.0276
No.0276.Paint Fence
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‎solution/0200-0299/0276.Paint Fence/README.md

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<!-- 这里可写通用的实现逻辑 -->
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**方法一：动态规划**
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定义 $dp[i][0]$ 表示栅栏 $[0,..i]$ 且最后两个栅栏颜色不同的方案数，$dp[i][1]$ 表示栅栏 $[0,..i]$ 且最后两个栅栏颜色相同的方案数。
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初始时 $dp[0][0]=k$。当 $i \ge 1$ 时，有：
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$$
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\begin{cases}
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dp[i][0]=(dp[i-1][0]+dp[i-1]) \times (k-1)\\
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dp[i][1]=dp[i-1][0]
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\end{cases}
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$$
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答案为 $dp[n-1][0] + dp[n-1][1]$。
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时间复杂度 $O(n)$，空间复杂度 $O(1)$。其中 $n$ 是栅栏柱的数量。
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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 Solution:
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def numWays(self, n: int, k: int) -> int:
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dp = [[0] * 2 for _ in range(n)]
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dp[0][0] = k
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for i in range(1, n):
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1)
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dp[i][1] = dp[i - 1][0]
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return sum(dp[-1])
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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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class Solution {
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public int numWays(int n, int k) {
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int[][] dp = new int[n][2];
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int numWays(int n, int k) {
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vector<vector<int>> dp(n, vector<int>(2));
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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};
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```
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### **Go**
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```go
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func numWays(n int, k int) int {
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, 2)
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}
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dp[0][0] = k
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for i := 1; i < n; i++ {
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dp[i][0] = (dp[i-1][0] + dp[i-1][1]) * (k - 1)
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dp[i][1] = dp[i-1][0]
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}
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return dp[n-1][0] + dp[n-1][1]
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}
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```
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### **...**

‎solution/0200-0299/0276.Paint Fence/README_EN.md

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### **Python3**
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```python
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class Solution:
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def numWays(self, n: int, k: int) -> int:
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dp = [[0] * 2 for _ in range(n)]
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dp[0][0] = k
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for i in range(1, n):
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1)
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dp[i][1] = dp[i - 1][0]
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return sum(dp[-1])
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```
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### **Java**
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```java
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class Solution {
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public int numWays(int n, int k) {
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int[][] dp = new int[n][2];
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int numWays(int n, int k) {
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vector<vector<int>> dp(n, vector<int>(2));
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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};
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```
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### **Go**
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```go
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func numWays(n int, k int) int {
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, 2)
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}
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dp[0][0] = k
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for i := 1; i < n; i++ {
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dp[i][0] = (dp[i-1][0] + dp[i-1][1]) * (k - 1)
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dp[i][1] = dp[i-1][0]
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}
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return dp[n-1][0] + dp[n-1][1]
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}
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```
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### **...**

‎solution/0200-0299/0276.Paint Fence/Solution.cpp

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class Solution {
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public:
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int numWays(int n, int k) {
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vector<vector<int>> dp(n, vector<int>(2));
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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};

‎solution/0200-0299/0276.Paint Fence/Solution.go

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func numWays(n int, k int) int {
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dp := make([][]int, n)
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for i := range dp {
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dp[i] = make([]int, 2)
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}
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dp[0][0] = k
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for i := 1; i < n; i++ {
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dp[i][0] = (dp[i-1][0] + dp[i-1][1]) * (k - 1)
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dp[i][1] = dp[i-1][0]
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}
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return dp[n-1][0] + dp[n-1][1]
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}

‎solution/0200-0299/0276.Paint Fence/Solution.java

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class Solution {
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public int numWays(int n, int k) {
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int[][] dp = new int[n][2];
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dp[0][0] = k;
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for (int i = 1; i < n; ++i) {
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1);
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dp[i][1] = dp[i - 1][0];
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}
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return dp[n - 1][0] + dp[n - 1][1];
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}
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}

‎solution/0200-0299/0276.Paint Fence/Solution.py

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class Solution:
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def numWays(self, n: int, k: int) -> int:
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dp = [[0] * 2 for _ in range(n)]
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dp[0][0] = k
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for i in range(1, n):
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dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) * (k - 1)
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dp[i][1] = dp[i - 1][0]
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return sum(dp[-1])

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