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feat: add solutions to lc problem: No.0294
No.0294.Flip Game II
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‎README.md

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- [公平分发饼干](/solution/2300-2399/2305.Fair%20Distribution%20of%20Cookies/README.md) - `DFS`、`回溯`、`剪枝`
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- [矩阵中的最长递增路径](/solution/0300-0399/0329.Longest%20Increasing%20Path%20in%20a%20Matrix/README.md) - `DFS`、`记忆化搜索`
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- [网格图中递增路径的数目](/solution/2300-2399/2328.Number%20of%20Increasing%20Paths%20in%20a%20Grid/README.md) - `DFS`、`记忆化搜索`
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- [翻转游戏 II](/solution/0200-0299/0294.Flip%20Game%20II/README.md) - `DFS`、`状态压缩`、`记忆化搜索`
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<!-- DFS 待补充 -->
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‎README_EN.md

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@@ -97,6 +97,7 @@ Complete solutions to [LeetCode](https://leetcode.com/problemset/all/), [LCOF](h
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- [Fair Distribution of Cookies](/solution/2300-2399/2305.Fair%20Distribution%20of%20Cookies/README_EN.md) - `DFS`, `Backtracking`
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- [Longest Increasing Path in a Matrix](/solution/0300-0399/0329.Longest%20Increasing%20Path%20in%20a%20Matrix/README_EN.md) - `DFS`、`Memoization`
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- [Number of Increasing Paths in a Grid](/solution/2300-2399/2328.Number%20of%20Increasing%20Paths%20in%20a%20Grid/README.md) - `DFS`、`Memoization`
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- [Flip Game II](/solution/0200-0299/0294.Flip%20Game%20II/README_EN.md) - `DFS`、`Bitmask`、`Memoization`
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### 4. Dynamic Programming(DP)
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‎solution/0200-0299/0294.Flip Game II/README.md

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<!-- 这里可写通用的实现逻辑 -->
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**方法一：状态压缩 + 记忆化搜索**
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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
54-
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class Solution:
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def canWin(self, currentState: str) -> bool:
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@cache
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def dfs(mask):
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for i in range(n - 1):
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if (mask & (1 << i)) == 0 or (mask & (1 << (i + 1)) == 0):
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continue
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if dfs(mask ^ (1 << i) ^ (1 << (i + 1))):
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continue
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return True
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return False
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mask, n = 0, len(currentState)
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for i, c in enumerate(currentState):
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if c == '+':
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mask |= 1 << i
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return dfs(mask)
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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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private int n;
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private Map<Long, Boolean> memo = new HashMap<>();
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public boolean canWin(String currentState) {
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long mask = 0;
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n = currentState.length();
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for (int i = 0; i < n; ++i) {
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if (currentState.charAt(i) == '+') {
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mask |= 1 << i;
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}
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}
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return dfs(mask);
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}
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private boolean dfs(long mask) {
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if (memo.containsKey(mask)) {
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return memo.get(mask);
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}
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for (int i = 0; i < n - 1; ++i) {
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if ((mask & (1 << i)) == 0 || (mask & (1 << (i + 1))) == 0) {
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continue;
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}
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if (dfs(mask ^ (1 << i) ^ (1 << (i + 1)))) {
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continue;
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}
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memo.put(mask, true);
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return true;
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}
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memo.put(mask, false);
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return false;
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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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using ll = long long;
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class Solution {
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public:
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int n;
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unordered_map<ll, bool> memo;
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bool canWin(string currentState) {
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n = currentState.size();
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ll mask = 0;
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for (int i = 0; i < n; ++i) if (currentState[i] == '+') mask |= 1ll << i;
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return dfs(mask);
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}
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bool dfs(ll mask) {
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if (memo.count(mask)) return memo[mask];
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for (int i = 0; i < n - 1; ++i)
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{
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if ((mask & (1ll << i)) == 0 || (mask & (1ll << (i + 1))) == 0) continue;
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if (dfs(mask ^ (1ll << i) ^ (1ll << (i + 1)))) continue;
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memo[mask] = true;
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return true;
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}
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memo[mask] = false;
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return false;
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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 canWin(currentState string) bool {
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n := len(currentState)
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memo := map[int]bool{}
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mask := 0
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for i, c := range currentState {
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if c == '+' {
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mask |= 1 << i
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}
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}
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var dfs func(int) bool
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dfs = func(mask int) bool {
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if v, ok := memo[mask]; ok {
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return v
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}
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for i := 0; i < n-1; i++ {
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if (mask&(1<<i)) == 0 || (mask&(1<<(i+1))) == 0 {
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continue
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}
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if dfs(mask ^ (1 << i) ^ (1 << (i + 1))) {
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continue
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}
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memo[mask] = true
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return true
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}
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memo[mask] = false
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return false
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}
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return dfs(mask)
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}
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```
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### **...**

‎solution/0200-0299/0294.Flip Game II/README_EN.md

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### **Python3**
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```python
47-
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class Solution:
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def canWin(self, currentState: str) -> bool:
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@cache
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def dfs(mask):
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for i in range(n - 1):
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if (mask & (1 << i)) == 0 or (mask & (1 << (i + 1)) == 0):
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continue
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if dfs(mask ^ (1 << i) ^ (1 << (i + 1))):
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continue
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return True
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return False
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mask, n = 0, len(currentState)
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for i, c in enumerate(currentState):
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if c == '+':
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mask |= 1 << i
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return dfs(mask)
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```
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### **Java**
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```java
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class Solution {
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private int n;
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private Map<Long, Boolean> memo = new HashMap<>();
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public boolean canWin(String currentState) {
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long mask = 0;
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n = currentState.length();
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for (int i = 0; i < n; ++i) {
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if (currentState.charAt(i) == '+') {
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mask |= 1 << i;
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}
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}
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return dfs(mask);
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}
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private boolean dfs(long mask) {
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if (memo.containsKey(mask)) {
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return memo.get(mask);
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}
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for (int i = 0; i < n - 1; ++i) {
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if ((mask & (1 << i)) == 0 || (mask & (1 << (i + 1))) == 0) {
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continue;
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}
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if (dfs(mask ^ (1 << i) ^ (1 << (i + 1)))) {
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continue;
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}
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memo.put(mask, true);
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return true;
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}
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memo.put(mask, false);
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return false;
100+
}
101+
}
102+
```
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### **C++**
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```cpp
107+
using ll = long long;
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class Solution {
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public:
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int n;
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unordered_map<ll, bool> memo;
113+
114+
bool canWin(string currentState) {
115+
n = currentState.size();
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ll mask = 0;
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for (int i = 0; i < n; ++i) if (currentState[i] == '+') mask |= 1ll << i;
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return dfs(mask);
119+
}
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bool dfs(ll mask) {
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if (memo.count(mask)) return memo[mask];
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for (int i = 0; i < n - 1; ++i)
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{
125+
if ((mask & (1ll << i)) == 0 || (mask & (1ll << (i + 1))) == 0) continue;
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if (dfs(mask ^ (1ll << i) ^ (1ll << (i + 1)))) continue;
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memo[mask] = true;
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return true;
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}
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memo[mask] = false;
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return false;
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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 canWin(currentState string) bool {
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n := len(currentState)
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memo := map[int]bool{}
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mask := 0
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for i, c := range currentState {
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if c == '+' {
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mask |= 1 << i
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}
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}
148+
var dfs func(int) bool
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dfs = func(mask int) bool {
150+
if v, ok := memo[mask]; ok {
151+
return v
152+
}
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for i := 0; i < n-1; i++ {
154+
if (mask&(1<<i)) == 0 || (mask&(1<<(i+1))) == 0 {
155+
continue
156+
}
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if dfs(mask ^ (1 << i) ^ (1 << (i + 1))) {
158+
continue
159+
}
160+
memo[mask] = true
161+
return true
162+
}
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memo[mask] = false
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return false
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}
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return dfs(mask)
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}
54168
```
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### **...**

‎solution/0200-0299/0294.Flip Game II/Solution.cpp

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using ll = long long;
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class Solution {
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public:
5+
int n;
6+
unordered_map<ll, bool> memo;
7+
8+
bool canWin(string currentState) {
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n = currentState.size();
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ll mask = 0;
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for (int i = 0; i < n; ++i) if (currentState[i] == '+') mask |= 1ll << i;
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return dfs(mask);
13+
}
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bool dfs(ll mask) {
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if (memo.count(mask)) return memo[mask];
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for (int i = 0; i < n - 1; ++i)
18+
{
19+
if ((mask & (1ll << i)) == 0 || (mask & (1ll << (i + 1))) == 0) continue;
20+
if (dfs(mask ^ (1ll << i) ^ (1ll << (i + 1)))) continue;
21+
memo[mask] = true;
22+
return true;
23+
}
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memo[mask] = false;
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return false;
26+
}
27+
};

‎solution/0200-0299/0294.Flip Game II/Solution.go

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func canWin(currentState string) bool {
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n := len(currentState)
3+
memo := map[int]bool{}
4+
mask := 0
5+
for i, c := range currentState {
6+
if c == '+' {
7+
mask |= 1 << i
8+
}
9+
}
10+
var dfs func(int) bool
11+
dfs = func(mask int) bool {
12+
if v, ok := memo[mask]; ok {
13+
return v
14+
}
15+
for i := 0; i < n-1; i++ {
16+
if (mask&(1<<i)) == 0 || (mask&(1<<(i+1))) == 0 {
17+
continue
18+
}
19+
if dfs(mask ^ (1 << i) ^ (1 << (i + 1))) {
20+
continue
21+
}
22+
memo[mask] = true
23+
return true
24+
}
25+
memo[mask] = false
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return false
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}
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return dfs(mask)
29+
}

‎solution/0200-0299/0294.Flip Game II/Solution.java

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class Solution {
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private int n;
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private Map<Long, Boolean> memo = new HashMap<>();
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5+
public boolean canWin(String currentState) {
6+
long mask = 0;
7+
n = currentState.length();
8+
for (int i = 0; i < n; ++i) {
9+
if (currentState.charAt(i) == '+') {
10+
mask |= 1 << i;
11+
}
12+
}
13+
return dfs(mask);
14+
}
15+
16+
private boolean dfs(long mask) {
17+
if (memo.containsKey(mask)) {
18+
return memo.get(mask);
19+
}
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for (int i = 0; i < n - 1; ++i) {
21+
if ((mask & (1 << i)) == 0 || (mask & (1 << (i + 1))) == 0) {
22+
continue;
23+
}
24+
if (dfs(mask ^ (1 << i) ^ (1 << (i + 1)))) {
25+
continue;
26+
}
27+
memo.put(mask, true);
28+
return true;
29+
}
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memo.put(mask, false);
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return false;
32+
}
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}

‎solution/0200-0299/0294.Flip Game II/Solution.py

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class Solution:
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def canWin(self, currentState: str) -> bool:
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@cache
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def dfs(mask):
5+
for i in range(n - 1):
6+
if (mask & (1 << i)) == 0 or (mask & (1 << (i + 1)) == 0):
7+
continue
8+
if dfs(mask ^ (1 << i) ^ (1 << (i + 1))):
9+
continue
10+
return True
11+
return False
12+
13+
mask, n = 0, len(currentState)
14+
for i, c in enumerate(currentState):
15+
if c == '+':
16+
mask |= 1 << i
17+
return dfs(mask)

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